diff --git a/active_projects/eola2/cramer.py b/active_projects/eola2/cramer.py
index fd4f1a7f..f836b56b 100644
--- a/active_projects/eola2/cramer.py
+++ b/active_projects/eola2/cramer.py
@@ -326,13 +326,13 @@ class SetupSimpleSystemOfEquations(LinearTransformationScene):
 
         self.add(system)
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, unknown_circles,
             lambda m: (m.restore,),
             lag_ratio=0.7
         ))
         self.play(FadeOut(unknown_circles))
-        self.play(LaggedStart(ShowCreation, row_rects,
+        self.play(OldLaggedStart(ShowCreation, row_rects,
                               run_time=1, lag_ratio=0.8))
         self.play(FadeOut(row_rects))
         self.wait()
@@ -818,7 +818,7 @@ class ThinkOfPuzzleAsLinearCombination(SetupSimpleSystemOfEquations):
                 lines[i].shift(basis_vectors[1 - i].get_end() - origin)
             return lines
         update_dashed_lines(dashed_lines)
-        self.play(LaggedStart(ShowCreation, dashed_lines, lag_ratio=0.7))
+        self.play(OldLaggedStart(ShowCreation, dashed_lines, lag_ratio=0.7))
         for basis in basis_vectors:
             self.play(
                 MoveToTarget(basis, run_time=2),
@@ -990,20 +990,20 @@ class LookAtDotProducts(SetupSimpleSystemOfEquations):
             MoveToTarget(corner_rect),
             Animation(self.equations),
             FadeOut(self.to_fade),
-            LaggedStart(Write, implications),
+            OldLaggedStart(Write, implications),
         )
         self.remove(self.input_vect_mob)
         self.apply_matrix(self.matrix, added_anims=[
             Animation(VGroup(corner_rect, self.equations, implications)),
             MoveToTarget(moving_equations[0]),
-            LaggedStart(FadeIn, transformed_equations[0].parts_to_write),
+            OldLaggedStart(FadeIn, transformed_equations[0].parts_to_write),
             FadeIn(self.column_mobs),
             ReplacementTransform(
                 self.input_vect_mob.copy(), self.output_vect_mob)
         ])
         self.play(
             MoveToTarget(moving_equations[1]),
-            LaggedStart(FadeIn, transformed_equations[1].parts_to_write),
+            OldLaggedStart(FadeIn, transformed_equations[1].parts_to_write),
             path_arc=-30 * DEGREES,
             run_time=2
         )
@@ -1011,7 +1011,7 @@ class LookAtDotProducts(SetupSimpleSystemOfEquations):
 
         # Show rectangles
         self.play(
-            LaggedStart(ShowCreation, transformed_input_rects, lag_ratio=0.8),
+            OldLaggedStart(ShowCreation, transformed_input_rects, lag_ratio=0.8),
             ShowCreation(self.output_vect_label.rect),
         )
         for tbr, column_mob in zip(transformed_basis_rects, self.column_mobs):
@@ -1265,7 +1265,7 @@ class SolvingASystemWithOrthonormalMatrix(LinearTransformationScene):
 
         self.apply_matrix(matrix)
         self.wait()
-        self.play(LaggedStart(ShowCreation, output_dashed_lines))
+        self.play(OldLaggedStart(ShowCreation, output_dashed_lines))
         self.play(*self.get_column_animations(system.matrix_mobject, column_mobs))
         self.wait()
         self.remove(*output_dashed_lines)
@@ -1325,7 +1325,7 @@ class SolvingASystemWithOrthonormalMatrix(LinearTransformationScene):
             anims = [
                 FadeIn(equation.background_rectangle),
                 Write(equation.to_write),
-                LaggedStart(
+                OldLaggedStart(
                     MoveToTarget, equation.movers,
                     path_arc=60 * DEGREES
                 )
@@ -1566,7 +1566,7 @@ class TransformingAreasYCoord(LinearTransformationScene):
         )
 
         # Fade out unneeded bits
-        self.play(LaggedStart(FadeOut, VGroup(
+        self.play(OldLaggedStart(FadeOut, VGroup(
             unit_brace, one, coord_brace, coord_brace.label,
         )))
 
@@ -1630,7 +1630,7 @@ class TransformingAreasYCoord(LinearTransformationScene):
 
         # Show many areas
         self.play(
-            LaggedStart(DrawBorderThenFill, blobs),
+            OldLaggedStart(DrawBorderThenFill, blobs),
             Write(area_scale_words)
         )
         self.add_transformable_mobject(blobs)
@@ -1671,7 +1671,7 @@ class TransformingAreasYCoord(LinearTransformationScene):
             Animation(basis_vectors),
             Animation(input_vect_mob),
             Write(q_marks),
-            LaggedStart(FadeOut, blobs),
+            OldLaggedStart(FadeOut, blobs),
         )
         self.transformable_mobjects.remove(blobs)
         self.play(
@@ -2005,7 +2005,7 @@ class ThreeDCoordinatesAsVolumes(Scene):
         coord_column[2].set_color(BLUE)
         coord_column.generate_target()
 
-        self.play(LaggedStart(FadeIn, VGroup(
+        self.play(OldLaggedStart(FadeIn, VGroup(
             z, equals, det_text, matrix.brackets,
             VGroup(*matrix.mob_matrix[:, :2].flatten()),
             coord_column
diff --git a/active_projects/eola2/determinant_puzzle.py b/active_projects/eola2/determinant_puzzle.py
index 29a7bc20..d5e5d6e2 100644
--- a/active_projects/eola2/determinant_puzzle.py
+++ b/active_projects/eola2/determinant_puzzle.py
@@ -63,7 +63,7 @@ class WorkOutNumerically(Scene):
         equation.set_width(FRAME_WIDTH - 2 * LARGE_BUFF)
         equation.next_to(self.original_equation, DOWN, MED_LARGE_BUFF)
 
-        self.play(LaggedStart(FadeIn, equation))
+        self.play(OldLaggedStart(FadeIn, equation))
 
     def compute_rhs(self):
         M1, M2 = self.M1_copy, self.M2_copy
@@ -101,15 +101,15 @@ class WorkOutNumerically(Scene):
                 for i, j in ((0, 0), (1, 1), (0, 1), (1, 0))
             ])
             self.play(
-                LaggedStart(FadeIn, non_numbers, run_time=1),
-                LaggedStart(
+                OldLaggedStart(FadeIn, non_numbers, run_time=1),
+                OldLaggedStart(
                     ReplacementTransform,
                     matrix_numbers,
                     lambda m: (m, next(numbers_iter)),
                     path_arc=TAU / 6
                 ),
             )
-        self.play(LaggedStart(FadeIn, lines[1:], run_time=3))
+        self.play(OldLaggedStart(FadeIn, lines[1:], run_time=3))
 
     def compute_lhs(self):
         matrix = Matrix([[-3, 7], [0, 5]])
@@ -138,7 +138,7 @@ class WorkOutNumerically(Scene):
             ReplacementTransform(M.copy(), matrix)
             for M in (self.M1, self.M2)
         ])
-        self.play(LaggedStart(FadeIn, group[1:]))
+        self.play(OldLaggedStart(FadeIn, group[1:]))
         self.wait()
 
 
diff --git a/active_projects/eop/bayes.py b/active_projects/eop/bayes.py
index 44058a6c..8ffd0f3b 100644
--- a/active_projects/eop/bayes.py
+++ b/active_projects/eop/bayes.py
@@ -55,7 +55,7 @@ class IntroducePokerHand(PiCreatureScene, SampleSpaceScene):
                 card.generate_target()
                 card.scale(0.01)
                 card.move_to(deck[-1], UP+RIGHT)
-            self.play(LaggedStart(MoveToTarget, group, lag_ratio = 0.8))
+            self.play(OldLaggedStart(MoveToTarget, group, lag_ratio = 0.8))
             self.wait()
         self.wait()
 
@@ -90,13 +90,13 @@ class IntroducePokerHand(PiCreatureScene, SampleSpaceScene):
         straight_cards.next_to(community_cards, UP, aligned_edge = LEFT)
         you.hand.target.shift(MED_SMALL_BUFF*UP)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             MoveToTarget,
             selected_community_cards,
             run_time = 1.5
         ))
         self.play(MoveToTarget(you.hand))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod,
             straight_cards,
             lambda m : (m.set_color, YELLOW),
@@ -147,7 +147,7 @@ class IntroducePokerHand(PiCreatureScene, SampleSpaceScene):
         self.play(heart_cards.shift, heart_cards.get_height()*UP)
         self.play(you.change_mode, "hesitant")
         self.play(MoveToTarget(her.hand))
-        self.play(LaggedStart(DrawBorderThenFill, heart_qs))
+        self.play(OldLaggedStart(DrawBorderThenFill, heart_qs))
         self.play(
             her.change, "happy",
             her.glasses.restore,
@@ -210,7 +210,7 @@ class IntroducePokerHand(PiCreatureScene, SampleSpaceScene):
             color = BLUE, buff = SMALL_BUFF
         )
 
-        self.play(LaggedStart(FadeIn, equation))
+        self.play(OldLaggedStart(FadeIn, equation))
         self.wait(2)
         self.play(
             FadeIn(num_hearts), 
@@ -305,7 +305,7 @@ class IntroducePokerHand(PiCreatureScene, SampleSpaceScene):
             dollar.move_to(her.get_boundary_point(RIGHT))
             dollar.set_fill(opacity = 0)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod,
             money,
             lambda m : (m.restore,),
@@ -480,7 +480,7 @@ class UpdatePokerPrior(SampleSpaceScene):
         braces_and_labels = sample_space.get_side_braces_and_labels(labels)
 
         self.play(
-            LaggedStart(FadeIn, sample_space),
+            OldLaggedStart(FadeIn, sample_space),
             Write(braces_and_labels)
         )
         self.wait()
@@ -748,7 +748,7 @@ class UpdatePokerPrior(SampleSpaceScene):
         group.arrange(DOWN)
         group.to_corner(UP+RIGHT)
 
-        self.play(LaggedStart(FadeIn, posterior_tex))
+        self.play(OldLaggedStart(FadeIn, posterior_tex))
         self.play(Write(arrow))
         self.play(MoveToTarget(rects[0]))
         self.wait()
@@ -859,7 +859,7 @@ class UpdatePokerPrior(SampleSpaceScene):
 
         self.wait(2)
         self.play(*list(map(FadeIn, [her, her.glasses])))
-        self.play(LaggedStart(FadeIn, risk_averse_words))
+        self.play(OldLaggedStart(FadeIn, risk_averse_words))
         self.play(her.change_mode, "sad", Animation(her.glasses))
         self.wait()
         self.play(ShowCreation(arrows))
@@ -1090,7 +1090,7 @@ class BayesRuleInMemory(Scene):
 
         self.add(randy)
         self.play(
-            LaggedStart(FadeIn, rule),
+            OldLaggedStart(FadeIn, rule),
             randy.change, "erm", rule
         )
         self.play(Blink(randy))
@@ -1497,7 +1497,7 @@ class GeneralizeBayesRule(SampleSpaceScene):
         post_rects = self.post_rects
 
         self.play(non_I_rects.fade, 0.8)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod,
             prior_rects,
             lambda m : (m.set_color, YELLOW),
@@ -1608,13 +1608,13 @@ class MusicExample(SampleSpaceScene, PiCreatureScene):
             word.scale(0.6)
             word.move_to(part)
 
-        self.play(LaggedStart(FadeIn, sample_space, run_time = 1))
+        self.play(OldLaggedStart(FadeIn, sample_space, run_time = 1))
         self.play(*list(map(GrowFromCenter, braces)))
         for label in labels:
             self.play(Write(label, run_time = 2))
             self.wait()
         for word, mode in zip(words, ["maybe", "soulful_musician"]):
-            self.play(LaggedStart(FadeIn, word, run_time = 1))
+            self.play(OldLaggedStart(FadeIn, word, run_time = 1))
             self.change_pi_creature_with_guitar(mode)
             self.wait()
         self.wait()
@@ -1644,7 +1644,7 @@ class MusicExample(SampleSpaceScene, PiCreatureScene):
             Animation(friends)
         )
         self.play_notes(randy.guitar)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, friends,
             lambda pi : (pi.change, "hooray"),
             run_time = 2,
@@ -1678,7 +1678,7 @@ class MusicExample(SampleSpaceScene, PiCreatureScene):
         VGroup(bubble, content).next_to(friends, LEFT, SMALL_BUFF)
         VGroup(bubble, content).to_edge(UP, SMALL_BUFF)
     
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, friends,
             lambda pi : (pi.change_mode, "conniving")
         ))
@@ -1687,7 +1687,7 @@ class MusicExample(SampleSpaceScene, PiCreatureScene):
             ShowCreation(bubble),
             Write(bubble.content, run_time = 1),
             ApplyMethod(friends[0].change_mode, "hooray"),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, VGroup(*friends[1:]),
                 lambda pi : (pi.change_mode, "happy")
             ),
@@ -1704,7 +1704,7 @@ class MusicExample(SampleSpaceScene, PiCreatureScene):
         pi2.target.change("hesitant", pi1.eyes)
         pi3.target.change("pondering", pi2.eyes)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             MoveToTarget, friends
         ))
         self.change_pi_creature_with_guitar("concerned_musician")
@@ -1751,7 +1751,7 @@ class MusicExample(SampleSpaceScene, PiCreatureScene):
 
         self.change_pi_creature_with_guitar(
             "soulful_musician",
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, friends, 
                 lambda pi : (pi.change, "happy"),
                 run_time = 1,
@@ -1770,7 +1770,7 @@ class MusicExample(SampleSpaceScene, PiCreatureScene):
         negative_space.save_state()
 
         self.play(negative_space.fade, 0.8)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, positive_space,
             lambda m : (m.set_color, YELLOW),
             rate_func = there_and_back,
@@ -1909,7 +1909,7 @@ class MusicExample(SampleSpaceScene, PiCreatureScene):
         self.play(ShowCreation(post_rect))
         self.wait(2)
         for mode, time in ("shruggie", 2), ("hesitant", 0):
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 ApplyMethod, friends,
                 lambda pi : (pi.change, mode),
                 run_time = 2,
@@ -1961,7 +1961,7 @@ class MusicExample(SampleSpaceScene, PiCreatureScene):
         brace = braces[0]
 
         self.play(old_prior_rects.fade, 0.8)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, friends,
             lambda pi : (pi.change, "pondering", post_rects),
             run_time = 1
@@ -2058,7 +2058,7 @@ class MusicExample(SampleSpaceScene, PiCreatureScene):
             notes.get_center() - \
             sine_wave.point_from_proportion(0)
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             MoveAlongPath, notes, 
             lambda n : (n, sine_wave),
             path_arc = np.pi/2,
diff --git a/active_projects/eop/bayes_footnote.py b/active_projects/eop/bayes_footnote.py
index 5a76fad2..144916a5 100644
--- a/active_projects/eop/bayes_footnote.py
+++ b/active_projects/eop/bayes_footnote.py
@@ -263,7 +263,7 @@ class OneInOneThousandHaveDisease(Scene):
         self.play(randy.restore)
         self.play(
             Write(title),
-            LaggedStart(FadeIn, all_creatures, run_time = 3)
+            OldLaggedStart(FadeIn, all_creatures, run_time = 3)
         )
         self.wait()
 
@@ -344,7 +344,7 @@ class TestNonDiseaseCase(TestScene):
         self.play(Blink(randy))
         self.play(
             ReplacementTransform(randy, all_creatures[0][0]),
-            LaggedStart(FadeIn, all_creatures, run_time = 2),
+            OldLaggedStart(FadeIn, all_creatures, run_time = 2),
             FadeOut(result)
         )
         self.play(ShowCreation(rect))
@@ -434,7 +434,7 @@ class RephraseQuestion(Scene):
 
         self.add(words[0])
         self.play(
-            LaggedStart(FadeIn, prior),
+            OldLaggedStart(FadeIn, prior),
             ShowCreation(prior_arrow),
             run_time = 1
         )
@@ -443,7 +443,7 @@ class RephraseQuestion(Scene):
         self.wait()
         self.play(FadeIn(words[2]))
         self.play(
-            LaggedStart(FadeIn, posterior),
+            OldLaggedStart(FadeIn, posterior),
             ShowCreation(posterior_arrow),
             run_time = 1
         )
@@ -568,7 +568,7 @@ class ShowRestrictedSpace(Scene):
         healthy_words.set_color(BLUE)
 
         self.add(title)
-        self.play(LaggedStart(FadeIn, all_creatures))
+        self.play(OldLaggedStart(FadeIn, all_creatures))
         self.play(
             FadeIn(sick_one_words),
             ShowCreation(sick_one_arrow)
@@ -582,7 +582,7 @@ class ShowRestrictedSpace(Scene):
         self.play(sick_one.restore)
         self.play(
             Write(healthy_words),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, healthy_creatures,
                 lambda m : (m.shift, MED_SMALL_BUFF*UP),
                 rate_func = there_and_back,
@@ -641,7 +641,7 @@ class ShowRestrictedSpace(Scene):
 
         self.play(
             GrowFromCenter(brace),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, false_positives,
                 lambda pi : (pi.set_color, self.false_positive_color),
                 run_time = 1
@@ -954,7 +954,7 @@ class ShowTheFormula(TeacherStudentsScene):
         #Show initial formula
         lhs_copy = lhs.copy()
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, initial_formula, 
                 lag_ratio = 0.7
             ),
@@ -975,7 +975,7 @@ class ShowTheFormula(TeacherStudentsScene):
             FadeIn(VGroup(*number_fraction[:3]))
         )
         self.wait(2)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, VGroup(*number_fraction[3:]),
             run_time = 3,
             lag_ratio = 0.7
@@ -1331,7 +1331,7 @@ class IntroduceTelepathyExample(StatisticsVsEmpathy):
         arcs.move_to(pi1.eyes, vect)
         arcs.set_stroke(WHITE, 4)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, arcs,
             lambda m : (m.restore,),
             lag_ratio = 0.7,
@@ -1375,7 +1375,7 @@ class CompareNumbersInBothExamples(Scene):
                 mob.shift(vect*FRAME_X_RADIUS/2)
 
         self.play(
-            LaggedStart(FadeIn, titles, lag_ratio = 0.7),
+            OldLaggedStart(FadeIn, titles, lag_ratio = 0.7),
             *list(map(ShowCreation, [h_line, v_line]))
         )
         self.wait()
@@ -1437,7 +1437,7 @@ class ExampleMeasuresDisbeliefInStatistics(Introduction):
         self.revert_to_original_skipping_status()
         self.play(bayes_to_intuition.to_edge, UP)
         self.play(
-            LaggedStart(FadeIn, statistics_to_belief),
+            OldLaggedStart(FadeIn, statistics_to_belief),
             cross.move_to, arrow
         )
         self.change_student_modes(
diff --git a/active_projects/eop/chapter1/area_model_bayes.py b/active_projects/eop/chapter1/area_model_bayes.py
index fe6a284d..e86adf21 100644
--- a/active_projects/eop/chapter1/area_model_bayes.py
+++ b/active_projects/eop/chapter1/area_model_bayes.py
@@ -43,7 +43,7 @@ class IllustrateAreaModelBayes(Scene):
         label_not_A = TexMobject("P(\\text{not }A)").next_to(brace_not_A, DOWN).scale(0.7)
 
         # self.play(
-        #     LaggedStart(FadeIn, VGroup(rect_A, rect_not_A), lag_factor = 0.5)
+        #     OldLaggedStart(FadeIn, VGroup(rect_A, rect_not_A), lag_factor = 0.5)
         # )
         # self.play(
         #     ShowCreation(brace_A),
@@ -75,7 +75,7 @@ class IllustrateAreaModelBayes(Scene):
         label_not_B = TexMobject("P(\\text{not }B)").next_to(brace_not_B, LEFT).scale(0.7)
 
         # self.play(
-        #     LaggedStart(FadeIn, VGroup(rect_B, rect_not_B), lag_factor = 0.5)
+        #     OldLaggedStart(FadeIn, VGroup(rect_B, rect_not_B), lag_factor = 0.5)
         # )
         # self.play(
         #     ShowCreation(brace_B),
diff --git a/active_projects/eop/chapter1/area_model_expectation.py b/active_projects/eop/chapter1/area_model_expectation.py
index 653e979f..3eb320a3 100644
--- a/active_projects/eop/chapter1/area_model_expectation.py
+++ b/active_projects/eop/chapter1/area_model_expectation.py
@@ -50,8 +50,8 @@ class IllustrateAreaModelExpectation(Scene):
             p_labels.add(p_label)
             
         self.play(
-            LaggedStart(FadeIn,braces),
-            LaggedStart(FadeIn, p_labels)
+            OldLaggedStart(FadeIn,braces),
+            OldLaggedStart(FadeIn, p_labels)
         )
 
 
diff --git a/active_projects/eop/chapter1/brick_row_scene.py b/active_projects/eop/chapter1/brick_row_scene.py
index 521d2b05..61cebe0e 100644
--- a/active_projects/eop/chapter1/brick_row_scene.py
+++ b/active_projects/eop/chapter1/brick_row_scene.py
@@ -246,7 +246,7 @@ class BrickRowScene(PiCreatureScene):
             coin_seqs.add(coin_seq)
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 Succession, coin_seqs, lambda m: (FadeIn(m, run_time = 0.1), MoveToTarget(m)),
                 run_time = 5,
                 lag_ratio = 0.5
@@ -446,7 +446,7 @@ class BrickRowScene(PiCreatureScene):
                 all_dice.add(dice_copy)
 
         self.play(
-            LaggedStart(FadeIn, all_dice),
+            OldLaggedStart(FadeIn, all_dice),
             FadeOut(outcomes[1])
         )
         self.wait()
@@ -709,7 +709,7 @@ class BrickRowScene(PiCreatureScene):
             inset = True)
         self.play(FadeOut(self.tallies))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, outcomes,
             #rate_func = there_and_back_with_pause,
             run_time = 5))
@@ -723,11 +723,11 @@ class BrickRowScene(PiCreatureScene):
 
 
         self.play(
-            LaggedStart(ShowCreation, braces),
-            LaggedStart(Write, probs)
+            OldLaggedStart(ShowCreation, braces),
+            OldLaggedStart(Write, probs)
         )
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeOut, outcomes,
             #rate_func = there_and_back_with_pause,
             run_time = 5),
@@ -749,7 +749,7 @@ class BrickRowScene(PiCreatureScene):
         # back to three coin flips, show all 8 outcomes
         run_time = 5
         self.play(
-            LaggedStart(FadeIn, outcomes,
+            OldLaggedStart(FadeIn, outcomes,
                 #rate_func = there_and_back_with_pause,
                 run_time = run_time),
             FadeOut(self.tallies,
@@ -757,7 +757,7 @@ class BrickRowScene(PiCreatureScene):
         )
         self.wait()
         self.play(
-            LaggedStart(FadeOut, outcomes,
+            OldLaggedStart(FadeOut, outcomes,
                 #rate_func = there_and_back_with_pause,
                 run_time = 5),
             FadeIn(self.tallies,
@@ -818,8 +818,8 @@ class BrickRowScene(PiCreatureScene):
         # for later reference
 
         self.play(
-            LaggedStart(FadeIn, grouped_outcomes),
-            LaggedStart(FadeIn, grouped_outcomes_copy),
+            OldLaggedStart(FadeIn, grouped_outcomes),
+            OldLaggedStart(FadeIn, grouped_outcomes_copy),
         )
         self.wait()
 
@@ -977,8 +977,8 @@ class ShowProbsInBrickRow3(BrickRowScene):
 
         self.wait()
         self.play(
-            LaggedStart(ShowCreation, braces, run_time = 3),
-            LaggedStart(Write, probs, run_time = 3)
+            OldLaggedStart(ShowCreation, braces, run_time = 3),
+            OldLaggedStart(Write, probs, run_time = 3)
         )
         self.wait()
 
@@ -1017,8 +1017,8 @@ class ShowOutcomesInBrickRow4(BrickRowScene):
 
 
         self.play(
-            LaggedStart(FadeIn, previous_outcomes),
-            LaggedStart(FadeIn, previous_outcomes_copy),
+            OldLaggedStart(FadeIn, previous_outcomes),
+            OldLaggedStart(FadeIn, previous_outcomes_copy),
         )
         
         self.wait()
diff --git a/active_projects/eop/chapter1/entire_brick_wall.py b/active_projects/eop/chapter1/entire_brick_wall.py
index 65aed6e7..98cb0a1a 100644
--- a/active_projects/eop/chapter1/entire_brick_wall.py
+++ b/active_projects/eop/chapter1/entire_brick_wall.py
@@ -71,7 +71,7 @@ class EntireBrickWall(BrickRowScene, MovingCameraScene):
         nb_tails_text.next_to(tails_counters[-1], RIGHT, buff = LARGE_BUFF)
 
         self.play(
-            LaggedStart(FadeIn, tails_counters),
+            OldLaggedStart(FadeIn, tails_counters),
             FadeIn(nb_tails_text)
         )
 
diff --git a/active_projects/eop/chapter1/prob_dist_visuals.py b/active_projects/eop/chapter1/prob_dist_visuals.py
index cbabe22e..38062aff 100644
--- a/active_projects/eop/chapter1/prob_dist_visuals.py
+++ b/active_projects/eop/chapter1/prob_dist_visuals.py
@@ -198,7 +198,7 @@ class ProbabilityDistributions(PiCreatureScene):
         #     cell.add(label)
 
         # self.play(
-        #     LaggedStart(FadeIn, dice_table_grouped_cells,
+        #     OldLaggedStart(FadeIn, dice_table_grouped_cells,
         #         lag_ratio = lag_ratio, run_time = run_time)
         # )
         self.play(
diff --git a/active_projects/eop/chapter1/quiz_result.py b/active_projects/eop/chapter1/quiz_result.py
index dad9ae72..1b231afe 100644
--- a/active_projects/eop/chapter1/quiz_result.py
+++ b/active_projects/eop/chapter1/quiz_result.py
@@ -200,7 +200,7 @@ class QuizResult(PiCreatureScene):
             for i in range(4)
         ])
         self.wait()
-        self.play(Write(nb_students_label), LaggedStart(GrowArrow,arrows))
+        self.play(Write(nb_students_label), OldLaggedStart(GrowArrow,arrows))
 
         percentage_label = TextMobject("\% of students", color = highlight_color)
         percentage_label.move_to(nb_students_label)
diff --git a/active_projects/eop/chapter1/show_uncertainty_darts.py b/active_projects/eop/chapter1/show_uncertainty_darts.py
index d206069a..1dbe44c7 100644
--- a/active_projects/eop/chapter1/show_uncertainty_darts.py
+++ b/active_projects/eop/chapter1/show_uncertainty_darts.py
@@ -20,7 +20,7 @@ class ShowUncertaintyDarts(Scene):
             self.add(dot)
 
         self.play(
-            LaggedStart(FadeIn, dots, lag_ratio = 0.01, run_time = run_time)
+            OldLaggedStart(FadeIn, dots, lag_ratio = 0.01, run_time = run_time)
         )
 
 
diff --git a/active_projects/eop/chapter1/show_uncertainty_dice.py b/active_projects/eop/chapter1/show_uncertainty_dice.py
index eafa1753..edb73f5b 100644
--- a/active_projects/eop/chapter1/show_uncertainty_dice.py
+++ b/active_projects/eop/chapter1/show_uncertainty_dice.py
@@ -59,5 +59,5 @@ class IdealizedDieHistogram(Scene):
 
 
         self.play(FadeIn(hist))
-        self.play(LaggedStart(FadeIn, hist.y_labels_group))
+        self.play(OldLaggedStart(FadeIn, hist.y_labels_group))
 
diff --git a/active_projects/eop/chapter1/show_uncertainty_disease.py b/active_projects/eop/chapter1/show_uncertainty_disease.py
index 6d5b9d20..c90e9baf 100644
--- a/active_projects/eop/chapter1/show_uncertainty_disease.py
+++ b/active_projects/eop/chapter1/show_uncertainty_disease.py
@@ -99,6 +99,6 @@ class OneIn200HasDisease(Scene):
         self.wait()
         self.play(
             Write(title),
-            LaggedStart(FadeIn, all_creatures, run_time = 3)
+            OldLaggedStart(FadeIn, all_creatures, run_time = 3)
         )
         self.wait()
diff --git a/active_projects/eop/chapter1/various_intro_visuals.py b/active_projects/eop/chapter1/various_intro_visuals.py
index aba40fe6..3fd5c43d 100644
--- a/active_projects/eop/chapter1/various_intro_visuals.py
+++ b/active_projects/eop/chapter1/various_intro_visuals.py
@@ -128,5 +128,5 @@ class BinaryChoices(Scene):
         all = all.scale(2)
 
         self.play(
-            LaggedStart(FadeIn, all)
+            OldLaggedStart(FadeIn, all)
         )
diff --git a/active_projects/eop/combinations.py b/active_projects/eop/combinations.py
index 4ec6c9a7..977dd793 100644
--- a/active_projects/eop/combinations.py
+++ b/active_projects/eop/combinations.py
@@ -131,7 +131,7 @@ class ExperienceProblemSolver(PiCreatureScene):
         cross = Cross(lightbulb)
         cross.set_stroke(RED, 8)
 
-        self.play(LaggedStart(ShowCreation, lightbulb))
+        self.play(OldLaggedStart(ShowCreation, lightbulb))
         self.play(
             ShowCreation(cross),
             jenny.change, "sassy", cross,
@@ -264,7 +264,7 @@ class InitialFiveChooseThreeExample(Scene):
             mover.add(group)
 
         self.play(FadeIn(nCk_group))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             MoveToTarget, mover,
             run_time = 3,
         ))
@@ -301,7 +301,7 @@ class InitialFiveChooseThreeExample(Scene):
         for line in stack:
             ones = VGroup(*[mob for mob in line if "1" in mob.get_tex_string()])
             line.ones = ones
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 ApplyMethod, ones,
                 lambda mob : (mob.set_color, YELLOW),
                 rate_func = there_and_back,
@@ -436,7 +436,7 @@ class SixChooseThreeExample(InitialFiveChooseThreeExample):
         equation.next_to(stack, RIGHT, LARGE_BUFF)
 
         self.add(equation)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, stack,
             lag_ratio = 0.1,
             run_time = 10,
@@ -471,7 +471,7 @@ class SixChooseThreeExample(InitialFiveChooseThreeExample):
             run_time = 1
         )
         self.play(
-            LaggedStart(GrowArrow, arrows),
+            OldLaggedStart(GrowArrow, arrows),
             Write(choose_k, run_time = 1)
         )
         self.wait(2)
@@ -712,7 +712,7 @@ class SixChooseThreeInOtherContext(Scene):
 #         self.play(ShowCreation(line))
 #         self.play(Write(add_x, run_time = 1))
 #         self.play(Transform(top_stacks, new_top_stacks))
-#         self.play(LaggedStart(
+#         self.play(OldLaggedStart(
 #             Indicate, new_top_stacks.start_terms,
 #             rate_func = there_and_back,
 #             run_time = 1,
@@ -721,7 +721,7 @@ class SixChooseThreeInOtherContext(Scene):
 #         self.wait()
 #         self.play(Write(add_y, run_time = 1))
 #         self.play(Transform(stacks, new_stacks))
-#         self.play(LaggedStart(
+#         self.play(OldLaggedStart(
 #             Indicate, new_stacks.start_terms,
 #             rate_func = there_and_back,
 #             run_time = 1,
@@ -852,7 +852,7 @@ class SixChooseThreeInOtherContext(Scene):
 #         self.play(Write(letter_set, run_time = 1))
 #         self.play(
 #             Write(choose_words, run_time = 1),
-#             LaggedStart(FadeIn, subset_mobs)
+#             OldLaggedStart(FadeIn, subset_mobs)
 #         )
 #         self.wait()
 #         for subset, subset_mob in zip(letter_subsets, subset_mobs):
@@ -950,7 +950,7 @@ class SixChooseThreeInOtherContext(Scene):
 #         words.next_to(cards, LEFT)
 #         words.shift_onto_screen()
 
-#         self.play(LaggedStart(DrawBorderThenFill, cards))
+#         self.play(OldLaggedStart(DrawBorderThenFill, cards))
 #         self.play(Write(words))
 #         self.wait(3)
 
@@ -992,7 +992,7 @@ class ProbabilityOfKWomenInGroupOfFive(Scene):
             return lineup
 
         last_lineup = get_lineup()
-        self.play(LaggedStart(FadeIn, last_lineup, run_time = 1))
+        self.play(OldLaggedStart(FadeIn, last_lineup, run_time = 1))
 
         for x in range(self.n_examples):
             lineup = get_lineup()
@@ -1073,7 +1073,7 @@ class ProbabilityOfKWomenInGroupOfFive(Scene):
                 else:
                     men.add(item)
             for group in men, women:
-                self.play(LaggedStart(
+                self.play(OldLaggedStart(
                     ApplyMethod, group,
                     lambda m : (m.shift, MED_SMALL_BUFF*RIGHT),
                     rate_func = there_and_back,
@@ -1152,7 +1152,7 @@ class ProbabilityOfKWomenInGroupOfFive(Scene):
                 lines.set_stroke, WHITE, 3,
                 Write(equation, run_time = 1)
             )
-            self.play(LaggedStart(Indicate, women, rate_func = there_and_back))
+            self.play(OldLaggedStart(Indicate, women, rate_func = there_and_back))
         self.wait()
 
         self.equations = equations
@@ -1165,7 +1165,7 @@ class ProbabilityOfKWomenInGroupOfFive(Scene):
         numbers = self.numbers
 
         self.play(ShowCreation(n_possibilities_rect))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Indicate, twos, 
             rate_func = wiggle
         ))
@@ -1231,8 +1231,8 @@ class ProbabilityOfKWomenInGroupOfFive(Scene):
         ])
         circles.set_color(WHITE)
 
-        self.play(LaggedStart(FadeIn, question))
-        self.play(LaggedStart(ShowCreationThenDestruction, circles))
+        self.play(OldLaggedStart(FadeIn, question))
+        self.play(OldLaggedStart(ShowCreationThenDestruction, circles))
         self.wait(2)
 
     ######
@@ -1323,14 +1323,14 @@ class TeacherHoldingSomething(TeacherStudentsScene):
 #             numbers.add(number)
 
 #         self.add(title)
-#         self.play(LaggedStart(
-#             LaggedStart, stacks,
+#         self.play(OldLaggedStart(
+#             OldLaggedStart, stacks,
 #             lambda s : (FadeIn, s),
 #             run_time = 3,
 #         ))
 #         self.play(Write(numbers, run_time = 3))
 #         self.wait()
-#         self.play(LaggedStart(
+#         self.play(OldLaggedStart(
 #             ApplyMethod, women_groups,
 #             lambda m : (m.set_color, PINK),
 #             lag_ratio = 0.1,
@@ -1578,7 +1578,7 @@ class BuildFiveFromFour(ProbabilityOfKWomenInGroupOfFive):
 
         new_numbers = VGroup()
 
-        self.play(LaggedStart(ShowCreation, rects, run_time = 1))
+        self.play(OldLaggedStart(ShowCreation, rects, run_time = 1))
         for i, top_stack in enumerate(top_stacks[:-1]):
             bottom_stack = bottom_stacks[i+1]
             top_number = top_stacks.numbers[i]
@@ -1848,7 +1848,7 @@ class IntroducePascalsTriangle(Scene):
         ))
         self.play(
             Blink(morty),
-            LaggedStart(
+            OldLaggedStart(
                 Indicate, numbers,
                 rate_func = wiggle,
                 color = PINK,
@@ -2197,10 +2197,10 @@ class ChooseThreeFromFive(InitialFiveChooseThreeExample, PiCreatureScene):
 
         self.play(
             Write(braces),
-            LaggedStart(FadeIn, people),
+            OldLaggedStart(FadeIn, people),
             VGroup(self.stack, self.equation).to_edge, RIGHT, LARGE_BUFF
         )
-        self.play(LaggedStart(FadeIn, names))
+        self.play(OldLaggedStart(FadeIn, names))
 
         self.set_variables_as_attrs(names, braces)
 
@@ -2226,7 +2226,7 @@ class ChooseThreeFromFive(InitialFiveChooseThreeExample, PiCreatureScene):
         if hasattr(self, "stack"):
             movers.target.align_to(self.stack, UP)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             MoveToTarget, movers,
             lag_ratio = 0.2,
             run_time = 4,
@@ -2264,7 +2264,7 @@ class ChooseThreeFromFive(InitialFiveChooseThreeExample, PiCreatureScene):
         self.play(ShowCreation(line_rect))
         self.play(MoveToTarget(line))
         self.play(
-            LaggedStart(ShowCreation, people_rects),
+            OldLaggedStart(ShowCreation, people_rects),
             MoveToTarget(people),
             MoveToTarget(names),
         )
@@ -2351,16 +2351,16 @@ class ChooseThreeFromFive(InitialFiveChooseThreeExample, PiCreatureScene):
         q_marks.set_color(YELLOW)
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ShowCreationThenDestruction, odm_words_outline,
                 lag_ratio = 0.2,
                 run_time = 1,
             ),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, self.people,
                 lambda pi : (pi.change, "confused", odm_words,)
             ),
-            LaggedStart(FadeIn, q_marks),
+            OldLaggedStart(FadeIn, q_marks),
         )
         self.play(line.next_to, odm_words, UP)
         for x in range(6):
@@ -2407,13 +2407,13 @@ class ChooseThreeFromFive(InitialFiveChooseThreeExample, PiCreatureScene):
             all_ones.add(ones)
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, all_ones,
                 lag_ratio = 0.2,
                 run_time = 3,
                 rate_func = there_and_back
             ),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, self.people,
                 lambda pi : (pi.change, "happy", ones),
             )
@@ -2742,7 +2742,7 @@ class HowToComputeNChooseK(ChooseThreeFromFive):
         for name, line, count, arrow in zip(chosen_names, lines, choice_counts, arrows):
             self.play(
                 FadeIn(count),
-                LaggedStart(
+                OldLaggedStart(
                     FadeIn, name_rects,
                     rate_func = there_and_back,
                     remover = True,
@@ -2908,7 +2908,7 @@ class HowToComputeNChooseK(ChooseThreeFromFive):
 
         self.play(
             Write(VGroup(*rhs[:-1])),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, all_groups,
                 lambda g : (g.restore,),
                 rate_func = lambda t : smooth(1-t),
@@ -2918,7 +2918,7 @@ class HowToComputeNChooseK(ChooseThreeFromFive):
         )
         self.wait()
         self.play(
-            LaggedStart(FadeIn, rects),
+            OldLaggedStart(FadeIn, rects),
             Write(rhs[-1])
         )
         self.wait()
@@ -3081,13 +3081,13 @@ class NineChooseFourExample(HowToComputeNChooseK):
 
         self.play(
             Write(braces),
-            LaggedStart(FadeIn, people, run_time = 1),
+            OldLaggedStart(FadeIn, people, run_time = 1),
             FadeIn(n_items),
         )
         self.wait()
         self.play(
             FadeIn(choose_k),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, chosen_subset,
                 lambda m : (m.shift, MED_LARGE_BUFF*DOWN)
             )
@@ -3102,8 +3102,8 @@ class NineChooseFourExample(HowToComputeNChooseK):
     def count_how_to_choose_k(self):
         lines, place_words = self.get_lines_and_place_words()
         self.play(
-            LaggedStart(FadeIn, lines),
-            LaggedStart(FadeIn, place_words),
+            OldLaggedStart(FadeIn, lines),
+            OldLaggedStart(FadeIn, place_words),
             run_time = 1
         )
         self.count_possibilities()
@@ -3192,9 +3192,9 @@ class WeirdKindOfCancelation(TeacherStudentsScene):
             RemovePiCreatureBubble(
                 self.teacher, target_mode = "raise_right_hand"
             ),
-            LaggedStart(FadeIn, fraction, run_time = 1),
+            OldLaggedStart(FadeIn, fraction, run_time = 1),
             FadeIn(braces),
-            LaggedStart(FadeIn, names)
+            OldLaggedStart(FadeIn, names)
         )
         self.change_student_modes(
             *["pondering"]*3,
@@ -3215,7 +3215,7 @@ class WeirdKindOfCancelation(TeacherStudentsScene):
         permutations = list(it.permutations(list(range(3))))[1:]
 
         self.shuffle(chosen_names, permutations[:2])
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreationThenDestruction,
             VGroup(*list(map(SurroundingRectangle, bottom_numbers[::2])))
         ))
@@ -3322,8 +3322,8 @@ class SumsToPowerOf2(Scene):
             number.next_to(stack, UP)
 
         self.play(
-            LaggedStart(FadeIn, stacks),
-            LaggedStart(FadeIn, numbers),
+            OldLaggedStart(FadeIn, stacks),
+            OldLaggedStart(FadeIn, numbers),
         )
         self.wait()
 
@@ -3429,11 +3429,11 @@ class SumsToPowerOf2(Scene):
         rhs.next_to(sum_group, RIGHT)
 
         self.play(
-            LaggedStart(FadeOut, self.stacks),
-            LaggedStart(FadeOut, self.numbers),
-            LaggedStart(FadeIn, sum_group),
+            OldLaggedStart(FadeOut, self.stacks),
+            OldLaggedStart(FadeOut, self.numbers),
+            OldLaggedStart(FadeIn, sum_group),
         )
-        self.play(LaggedStart(FadeIn, rhs))
+        self.play(OldLaggedStart(FadeIn, rhs))
         self.wait(2)
 
     ####
@@ -3489,7 +3489,7 @@ class AskWhyTheyAreCalledBinomial(TeacherStudentsScene):
         self.student_says(
             "Why are they called \\\\ ``binomial coefficients''?"
         )
-        self.play(LaggedStart(FadeIn, pascals))
+        self.play(OldLaggedStart(FadeIn, pascals))
         self.wait()
         self.play(
             FadeIn(example_binomials[0]),
@@ -3505,7 +3505,7 @@ class AskWhyTheyAreCalledBinomial(TeacherStudentsScene):
         #Name themn
         self.play(
             Write(binomial_word),
-            LaggedStart(GrowArrow, arrows)
+            OldLaggedStart(GrowArrow, arrows)
         )
         self.change_student_modes(*["pondering"]*3)
         self.play(Write(two_variables))
diff --git a/active_projects/eop/independence.py b/active_projects/eop/independence.py
index c84208dd..b3d249af 100644
--- a/active_projects/eop/independence.py
+++ b/active_projects/eop/independence.py
@@ -143,7 +143,7 @@ class DangerInProbability(Scene):
         self.play(Write(warning, run_time = 1))
         self.play(
             warning.next_to, probability, UP, LARGE_BUFF,
-            LaggedStart(FadeIn, probability)
+            OldLaggedStart(FadeIn, probability)
         )
         self.wait()
 
@@ -353,7 +353,7 @@ class IntroduceBinomial(Scene):
         chart.to_edge(LEFT)
         self.bar_chart = chart
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, VGroup(*it.chain(*chart)), 
             run_time = 2
         ))
@@ -499,7 +499,7 @@ class IntroduceQuiz(PiCreatureScene):
             group.to_corner(UP+LEFT)
 
         self.play(
-            LaggedStart(FadeIn, probabilities, run_time = 3),
+            OldLaggedStart(FadeIn, probabilities, run_time = 3),
             self.quiz.set_height, 0.7*self.randy.get_height(),
             self.quiz.next_to, self.randy, RIGHT,
             self.randy.change, "confused", probabilities
@@ -523,7 +523,7 @@ class IntroduceQuiz(PiCreatureScene):
             short_p.next_to(bar, UP)
 
         self.play(
-            LaggedStart(Write, VGroup(
+            OldLaggedStart(Write, VGroup(
                 *[m for m in chart if m is not chart.bars]
             )),
         )
@@ -693,7 +693,7 @@ class AssociatePatternsWithScores(BreakDownQuestionPatterns):
                 ReplacementTransform(
                     score_group.copy(), score_group.organized
                 ),
-                LaggedStart(FadeIn, score, run_time = 1)
+                OldLaggedStart(FadeIn, score, run_time = 1)
             )
             self.play(score_group.restore)
         self.wait()
@@ -725,7 +725,7 @@ class AssociatePatternsWithScores(BreakDownQuestionPatterns):
         )
         self.play(
             self.randy.change, "pondering",
-            LaggedStart(FadeIn, triangle, run_time = 4),
+            OldLaggedStart(FadeIn, triangle, run_time = 4),
         )
         self.play(row.set_color, YELLOW)
         self.wait(4)
@@ -753,7 +753,7 @@ class BeforeCounting(TeacherStudentsScene):
         self.play(Write(prob))
         self.play(
             GrowFromCenter(brace),
-            LaggedStart(FadeIn, q_marks)
+            OldLaggedStart(FadeIn, q_marks)
         )
         self.wait(2)
 
@@ -806,7 +806,7 @@ class TemptingButWrongCalculation(BreakDownQuestionPatterns):
         self.play(
             Write(lhs),
             ShowCreation(slot_group.lines),
-            LaggedStart(FadeIn, slot_group.content, run_time = 3),
+            OldLaggedStart(FadeIn, slot_group.content, run_time = 3),
             self.randy.change, "pondering"
         )
         self.wait(2)
@@ -886,7 +886,7 @@ class ThousandPossibleQuizzes(Scene):
             FadeIn(title)
         )
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, quizzes, 
                 run_time = 3,
                 lag_ratio = 0.2,
@@ -993,7 +993,7 @@ class ThousandPossibleQuizzes(Scene):
             MoveToTarget(right_split),
         )
         self.play(FadeIn(left_label))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, left_split,
             lambda m : (m.set_color, YELLOW),
             rate_func = there_and_back,
@@ -1197,7 +1197,7 @@ class ThousandPossibleQuizzes(Scene):
         for split in all_splits:
             self.play(MoveToTarget(split))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, all_right,
             lambda m : (m.set_color, YELLOW),
             rate_func = there_and_back,
@@ -1520,7 +1520,7 @@ class ShowAllEightConditionals(Scene):
         )
         rect.shift(0.5*SMALL_BUFF*RIGHT)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, equations,
             run_time = 5,
             lag_ratio = 0.3
@@ -1629,7 +1629,7 @@ class ComputeProbabilityOfOneWrong(Scene):
             ))
         self.wait()
         for group in point_8s, point_2s:
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 Indicate, group,
                 rate_func = there_and_back,
                 lag_ratio = 0.7
@@ -1728,7 +1728,7 @@ class ShowFullDistribution(Scene):
         p_slot_group.next_to(brace, vect)
         group = VGroup(*it.chain(p_slot_group, brace, score))
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, group,
             run_time = 2,
             lag_ratio = 0.7,
@@ -1768,7 +1768,7 @@ class ShowFullDistribution(Scene):
             )
         )
         self.play(
-            LaggedStart(FadeIn, VGroup(*it.chain(*[
+            OldLaggedStart(FadeIn, VGroup(*it.chain(*[
                 submob 
                 for submob in chart
                 if submob is not chart.bars
@@ -1797,8 +1797,8 @@ class ShowFullDistribution(Scene):
         bars_copy = bars.copy()
 
         self.play(
-            LaggedStart(FadeIn, bars),
-            LaggedStart(FadeIn, nums),
+            OldLaggedStart(FadeIn, bars),
+            OldLaggedStart(FadeIn, nums),
         )
         self.wait(2)
         self.play(bars_copy.shift, -vect)
@@ -1868,7 +1868,7 @@ class ShowFullDistribution(Scene):
                 last = prob
                 buff = SMALL_BUFF
 
-        self.play(LaggedStart(FadeIn, probs))
+        self.play(OldLaggedStart(FadeIn, probs))
         self.wait()
         return probs
 
@@ -2324,7 +2324,7 @@ class NameBinomial(Scene):
         faded_checkmarks = VGroup(*[m for m in checkmarks if m not in full_checks])
 
         self.play(*[
-            LaggedStart(
+            OldLaggedStart(
                 Write, mob,
                 run_time = 3,
                 lag_ratio = 0.3
@@ -2333,7 +2333,7 @@ class NameBinomial(Scene):
         ])
         self.wait()
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 Rotate, flipped_arrows,
                 angle = np.pi,
                 in_place = True,
@@ -2440,7 +2440,7 @@ class NameBinomial(Scene):
 
 
         self.play(ShowCreation(chart_rect))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreation, girl_rects,
             run_time = 2,
             lag_ratio = 0.5,
@@ -2448,7 +2448,7 @@ class NameBinomial(Scene):
         self.wait()
 
         self.play(Write(prob))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Indicate, girls,
             run_time = 3,
             lag_ratio = 0.3,
@@ -2775,7 +2775,7 @@ class GeneralBinomialDistributionValues(Scene):
 
         self.play(FadeIn(shown_prob))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, self.full_probability,
             run_time = 4,
             lag_ratio = 0.5,
@@ -2810,7 +2810,7 @@ class GeneralBinomialDistributionValues(Scene):
         ten_choose_ks.set_color_by_gradient(BLUE, YELLOW)
 
         self.play(
-            LaggedStart(FadeIn, triangle),
+            OldLaggedStart(FadeIn, triangle),
             FadeOut(self.shown_prob)
         )
         self.play(
@@ -2820,7 +2820,7 @@ class GeneralBinomialDistributionValues(Scene):
         self.wait()
         self.play(ApplyWave(self.chart.bars, direction = UP))
         self.play(FocusOn(last_row))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, last_row,
             lambda m : (m.scale_in_place, 1.2),
             rate_func = there_and_back,
@@ -3099,7 +3099,7 @@ class CorrectForDependence(NameBinomial):
         if len(indices) > 1:
             kwargs.update({"run_time" : 2})
         return [
-            LaggedStart(
+            OldLaggedStart(
                 MoveToTarget, mover,
                 **kwargs
             )
@@ -3221,7 +3221,7 @@ class AssumeOrderDoesntMatter(Scene):
 
     def coming_soon(self):
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, self.assumption_group,
                 lambda m : (m.shift, FRAME_HEIGHT*DOWN),
                 remover = True,
diff --git a/active_projects/shadows.py b/active_projects/shadows.py
index 3dd58552..3d80f9bd 100644
--- a/active_projects/shadows.py
+++ b/active_projects/shadows.py
@@ -150,7 +150,7 @@ class ShowShadows(ThreeDScene):
         self.move_camera(
             **self.initial_orientation_config,
             added_anims=[
-                LaggedStart(DrawBorderThenFill, obj3d)
+                OldLaggedStart(DrawBorderThenFill, obj3d)
             ],
             run_time=2
         )
@@ -275,7 +275,7 @@ class ShowInfinitelyFarLightSource(ShowShadows):
         source_obj3d.set_shade_in_3d(False)
         source_obj3d.fade(1)
 
-        self.play(LaggedStart(ShowCreation, lines))
+        self.play(OldLaggedStart(ShowCreation, lines))
         self.wait()
         self.add(source_obj3d, lines)
         self.play(
diff --git a/example_scenes.py b/example_scenes.py
index 1f91cbcb..d80c93a2 100644
--- a/example_scenes.py
+++ b/example_scenes.py
@@ -31,7 +31,7 @@ class OpeningManimExample(Scene):
         transform_title.to_corner(UP + LEFT)
         self.play(
             Transform(title, transform_title),
-            LaggedStart(FadeOutAndShiftDown, basel),
+            OldLaggedStart(FadeOutAndShiftDown, basel),
         )
         self.wait()
 
diff --git a/manimlib/animation/composition.py b/manimlib/animation/composition.py
index 25dd3a58..444f5635 100644
--- a/manimlib/animation/composition.py
+++ b/manimlib/animation/composition.py
@@ -88,9 +88,9 @@ class Succession(AnimationGroup):
 # Variants on mapping an animation over submobjects
 
 
-# This class is depricated.  One should use LaggedStart
+# This class is depricated.  One should use OldLaggedStart
 # instead, which has different syntax, but more generality
-class LaggedStart(Animation):
+class OldLaggedStart(Animation):
     CONFIG = {
         "run_time": 2,
         "lag_ratio": 0.5,
diff --git a/manimlib/animation/specialized.py b/manimlib/animation/specialized.py
index 0566e708..122b4a55 100644
--- a/manimlib/animation/specialized.py
+++ b/manimlib/animation/specialized.py
@@ -1,4 +1,4 @@
-from manimlib.animation.composition import LaggedStart
+from manimlib.animation.composition import OldLaggedStart
 from manimlib.animation.transform import ApplyMethod
 from manimlib.constants import *
 from manimlib.mobject.geometry import Circle
@@ -32,7 +32,7 @@ class MoveCar(ApplyMethod):
             tire.rotate_in_place(radians)
 
 
-class Broadcast(LaggedStart):
+class Broadcast(OldLaggedStart):
     CONFIG = {
         "small_radius": 0.0,
         "big_radius": 5,
@@ -59,7 +59,7 @@ class Broadcast(LaggedStart):
             circle.set_width(self.small_radius * 2)
             circle.set_stroke(self.color, self.start_stroke_width)
             circles.add(circle)
-        LaggedStart.__init__(
+        OldLaggedStart.__init__(
             self, ApplyMethod, circles,
             lambda c: (c.restore,),
             **kwargs
diff --git a/manimlib/for_3b1b_videos/common_scenes.py b/manimlib/for_3b1b_videos/common_scenes.py
index 71ad8aed..d4e6699a 100644
--- a/manimlib/for_3b1b_videos/common_scenes.py
+++ b/manimlib/for_3b1b_videos/common_scenes.py
@@ -1,6 +1,6 @@
 import random
 
-from manimlib.animation.composition import LaggedStart
+from manimlib.animation.composition import OldLaggedStart
 from manimlib.animation.creation import DrawBorderThenFill
 from manimlib.animation.creation import FadeIn
 from manimlib.animation.creation import FadeOut
@@ -133,7 +133,7 @@ class PatreonThanks(Scene):
                     DrawBorderThenFill(patreon_logo),
                 ]
             self.play(
-                LaggedStart(
+                OldLaggedStart(
                     FadeIn, group,
                     run_time=2,
                 ),
diff --git a/manimlib/once_useful_constructs/light.py b/manimlib/once_useful_constructs/light.py
index 56f2b6e8..340fb437 100644
--- a/manimlib/once_useful_constructs/light.py
+++ b/manimlib/once_useful_constructs/light.py
@@ -2,7 +2,7 @@ from traceback import *
 
 from scipy.spatial import ConvexHull
 
-from manimlib.animation.composition import LaggedStart
+from manimlib.animation.composition import OldLaggedStart
 from manimlib.animation.creation import FadeIn
 from manimlib.animation.creation import FadeOut
 from manimlib.animation.transform import Transform
@@ -44,7 +44,7 @@ def inverse_quadratic(maxint, scale, cutoff):
     return inverse_power_law(maxint, scale, cutoff, 2)
 
 
-class SwitchOn(LaggedStart):
+class SwitchOn(OldLaggedStart):
     CONFIG = {
         "lag_ratio": 0.2,
         "run_time": SWITCH_ON_RUN_TIME
@@ -54,12 +54,12 @@ class SwitchOn(LaggedStart):
         if (not isinstance(light, AmbientLight) and not isinstance(light, Spotlight)):
             raise Exception(
                 "Only AmbientLights and Spotlights can be switched on")
-        LaggedStart.__init__(
+        OldLaggedStart.__init__(
             self, FadeIn, light, **kwargs
         )
 
 
-class SwitchOff(LaggedStart):
+class SwitchOff(OldLaggedStart):
     CONFIG = {
         "lag_ratio": 0.2,
         "run_time": SWITCH_ON_RUN_TIME
@@ -70,7 +70,7 @@ class SwitchOff(LaggedStart):
             raise Exception(
                 "Only AmbientLights and Spotlights can be switched off")
         light.submobjects = light.submobjects[::-1]
-        LaggedStart.__init__(self,
+        OldLaggedStart.__init__(self,
                              FadeOut, light, **kwargs)
         light.submobjects = light.submobjects[::-1]
 
diff --git a/old_projects/256.py b/old_projects/256.py
index 10b2955d..25aa42de 100644
--- a/old_projects/256.py
+++ b/old_projects/256.py
@@ -154,7 +154,7 @@ class BreakUp2To256(PiCreatureScene):
         self.play(
             self.bits.to_corner, DOWN+LEFT,
             Transform(four_billions, target_four_billions),
-            LaggedStart(FadeIn, parens),
+            OldLaggedStart(FadeIn, parens),
             FadeOut(to_fade)
         )
         self.wait()
@@ -331,7 +331,7 @@ class MainBreakdown(Scene):
         )
         self.wait()
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ApplyFunction, gpus,
                 lambda g : (
                     lambda m : m.scale(0.01).move_to(laptop),
@@ -384,7 +384,7 @@ class MainBreakdown(Scene):
         self.wait(2)
         self.play(Write(millions))
         self.wait(2)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Indicate, self.group_of_four_billion_things,
             run_time = 4,
             rate_func = there_and_back,
@@ -454,7 +454,7 @@ class MainBreakdown(Scene):
         self.play(FadeIn(milky_way))
         self.play(Write(n_stars_estimate))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Indicate, self.group_of_four_billion_things,
             rate_func = there_and_back,
             lag_ratio = 0.2,
@@ -580,7 +580,7 @@ class MainBreakdown(Scene):
             four_billion.scale, 2,
             four_billion.next_to, brace, LEFT,
             GrowFromCenter(brace),
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, group,
                 run_time = 3,
                 lag_ratio = 0.2
@@ -731,7 +731,7 @@ class StateOfBitcoin(TeacherStudentsScene):
             rate.restore,
         )
         self.change_student_modes(*["pondering"]*3)
-        self.play(LaggedStart(FadeIn, kilogoogle))
+        self.play(OldLaggedStart(FadeIn, kilogoogle))
         self.change_student_modes(*["surprised"]*3)
         self.wait()
         self.change_student_modes(
@@ -758,7 +758,7 @@ class StateOfBitcoin(TeacherStudentsScene):
             *["pondering"]*3,
             added_anims = [Write(asic_rate)]
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, circuit,
             run_time = 3,
             lag_ratio = 0.2,
diff --git a/old_projects/WindingNumber.py b/old_projects/WindingNumber.py
index 9b7a4c3a..ae9b3d58 100644
--- a/old_projects/WindingNumber.py
+++ b/old_projects/WindingNumber.py
@@ -2004,7 +2004,7 @@ class LoopSplitScene(ColorMappedObjectsScene):
             play_combined_fade(start, end, midline_lines_vmobject, midline_bullets)
 
         def flash_circles(circles):
-            self.play(LaggedStart(FadeIn, VGroup(circles)))
+            self.play(OldLaggedStart(FadeIn, VGroup(circles)))
             self.wait()
             self.play(FadeOut(VGroup(circles)))
             self.wait()
diff --git a/old_projects/WindingNumber_G.py b/old_projects/WindingNumber_G.py
index a010de44..d10ef55c 100644
--- a/old_projects/WindingNumber_G.py
+++ b/old_projects/WindingNumber_G.py
@@ -108,7 +108,7 @@ class IntroSceneWrapper(PiCreatureScene):
 
         self.play(Write(solver))
         self.play(
-            LaggedStart(FadeIn, xy_equation, run_time = 1),
+            OldLaggedStart(FadeIn, xy_equation, run_time = 1),
             morty.change, "pondering"
         )
         self.wait(2)
@@ -129,7 +129,7 @@ class IntroSceneWrapper(PiCreatureScene):
         self.play(solver.restore)
         self.wait()
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeOut, VGroup(solver, z_equation, zeta)
         ))
         self.play(
@@ -879,8 +879,8 @@ class IntroduceInputOutputScene(InputOutputScene):
         function_label.add_background_rectangle()
 
 
-        self.play(LaggedStart(GrowFromCenter, dots))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(GrowFromCenter, dots))
+        self.play(OldLaggedStart(
             MoveToTarget, dots,
             path_arc = path_arc
         ))
@@ -1053,7 +1053,7 @@ class IntroduceVectorField(IntroduceInputOutputScene):
             factor = target_length / vector.get_length()
             vector.target.scale(factor, about_point = vector.get_start())
 
-        self.play(LaggedStart(MoveToTarget, newer_in_vectors))
+        self.play(OldLaggedStart(MoveToTarget, newer_in_vectors))
         self.wait()
 
 class TwoDScreenInOurThreeDWorld(AltTeacherStudentsScene, ThreeDScene):
@@ -1114,10 +1114,10 @@ class TwoDScreenInOurThreeDWorld(AltTeacherStudentsScene, ThreeDScene):
             )
         )
         self.play(
-            LaggedStart(GrowFromCenter, dots, run_time = 1),
+            OldLaggedStart(GrowFromCenter, dots, run_time = 1),
             self.get_student_changes(*3*["erm"]),
         )
-        self.play(LaggedStart(MoveToTarget, dots, path_arc = -TAU/4))
+        self.play(OldLaggedStart(MoveToTarget, dots, path_arc = -TAU/4))
         self.wait(3)
 
 
@@ -1188,8 +1188,8 @@ class EveryOutputPointHasAColor(ColorMappedObjectsScene):
         while n <= len(dots):
             dot_groups.add(dots[n-1:m*n-1])
             n *= m
-        self.play(LaggedStart(
-            LaggedStart, dot_groups,
+        self.play(OldLaggedStart(
+            OldLaggedStart, dot_groups,
             lambda dg : (GrowFromCenter,  dg),
             run_time = 8,
             lag_ratio = 0.2,
@@ -1225,22 +1225,22 @@ class DotsHoppingToColor(InputOutputScene):
             output_plane.lines_to_fade.set_stroke, {"width" : 0},
         )
         self.wait()
-        self.play(LaggedStart(GrowFromCenter, dots, run_time = 3))
+        self.play(OldLaggedStart(GrowFromCenter, dots, run_time = 3))
         self.wait()
 
         #Hop over and back
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             MoveToTarget, dots, 
             path_arc = -TAU/4,
             run_time = 3,
         ))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, dots,
             lambda d : (d.set_fill, d.target_color),
         ))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, dots,
             lambda d : (d.move_to, d.original_position),
             path_arc = TAU/4,
@@ -1352,11 +1352,11 @@ class DotsHoppingToColor(InputOutputScene):
         self.play(
             FadeOut(input_coloring),
             input_plane.white_parts.set_color, WHITE,
-            LaggedStart(GrowFromCenter, dots)
+            OldLaggedStart(GrowFromCenter, dots)
         )
         self.wait()
         random.shuffle(dots.submobjects)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeOut, dots,
             lag_ratio = 0.05,
             run_time = 10,
@@ -1747,10 +1747,10 @@ class HypothesisAboutFullyColoredBoundary(ColorMappedObjectsScene):
 
         self.add(hypothesis[0])
         self.play(
-            LaggedStart(FadeIn, hypothesis[1]),
+            OldLaggedStart(FadeIn, hypothesis[1]),
             ShowCreation(square, run_time = 8)
         )
-        self.play(LaggedStart(FadeIn, hypothesis[2]))
+        self.play(OldLaggedStart(FadeIn, hypothesis[2]))
         self.play(square.set_fill, {"opacity" : 1}, run_time = 2)
         self.wait()
 
@@ -1965,8 +1965,8 @@ class FailureOfComposition(ColorMappedObjectsScene):
 
 
         self.add(question)
-        self.play(LaggedStart(ShowCreation, small_squares, lag_ratio = 0.8))
-        self.play(LaggedStart(Write, no_answers))
+        self.play(OldLaggedStart(ShowCreation, small_squares, lag_ratio = 0.8))
+        self.play(OldLaggedStart(Write, no_answers))
         self.wait()
         self.play(
             small_squares.arrange, DOWN, {"buff" : 0},
@@ -1985,7 +1985,7 @@ class FailureOfComposition(ColorMappedObjectsScene):
             Write(yes_answers),
             Write(yes_answers_in_equation),
         )
-        self.play(LaggedStart(FadeIn, q_marks, run_time = 1, lag_ratio = 0.8))
+        self.play(OldLaggedStart(FadeIn, q_marks, run_time = 1, lag_ratio = 0.8))
         self.wait(2)
         self.play(
             small_squares.restore,
@@ -2671,7 +2671,7 @@ class SearchSpacePerimeterVsArea(EquationSolver2d):
         self.remove(all_parts)
         for x in range(2):
             alt_path_parts.save_state()
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 FadeIn, alt_path_parts,
                 rate_func = there_and_back,
                 lag_ratio = 0.3,
@@ -2754,7 +2754,7 @@ class ShowComplexFunction(Scene):
         self.play(
             Write(plane),
             FadeIn(rect),
-            LaggedStart(FadeIn, title)
+            OldLaggedStart(FadeIn, title)
         )
         self.play(*list(map(FadeIn, [x_dot, x_label])))
         self.wait()
@@ -2900,7 +2900,7 @@ class AllOfTheVideos(Scene):
         images.set_height(FRAME_HEIGHT)
         random.shuffle(images.submobjects)
 
-        self.play(LaggedStart(FadeIn, images, run_time = 4))
+        self.play(OldLaggedStart(FadeIn, images, run_time = 4))
         self.wait()
 
 class EndingCredits(Scene):
@@ -2918,7 +2918,7 @@ class EndingCredits(Scene):
         pi.change_mode("happy")
         self.add(pi)
 
-        self.play(LaggedStart(FadeIn, text), pi.look_at, text)
+        self.play(OldLaggedStart(FadeIn, text), pi.look_at, text)
         self.play(pi.change, "wave_1", text)
         self.play(Blink(pi))
         self.play(pi.change, "happy")
@@ -2950,7 +2950,7 @@ class MentionQAndA(Scene):
         questions.arrange(DOWN, buff = 0.75)
         questions.next_to(title, DOWN, LARGE_BUFF)
 
-        self.play(LaggedStart(FadeIn, questions, run_time = 3))
+        self.play(OldLaggedStart(FadeIn, questions, run_time = 3))
         self.wait(2)
         self.play(FadeOut(questions))
         self.wait()
@@ -3002,7 +3002,7 @@ class InfiniteListOfTopics(Scene):
         lines[-1].next_to(lines[-2], DOWN)
 
         self.add(rect, title)
-        self.play(LaggedStart(FadeIn, lines, run_time = 5))
+        self.play(OldLaggedStart(FadeIn, lines, run_time = 5))
         self.wait()
 
 class ManyIterations(Scene):
diff --git a/old_projects/alt_calc.py b/old_projects/alt_calc.py
index f581c2f9..0faaf753 100644
--- a/old_projects/alt_calc.py
+++ b/old_projects/alt_calc.py
@@ -330,7 +330,7 @@ class NumberlineTransformationScene(ZoomedScene):
 
         # Add tiny dots
         if local_sample_dots is not None:
-            anims.append(LaggedStart(GrowFromCenter, local_sample_dots))
+            anims.append(OldLaggedStart(GrowFromCenter, local_sample_dots))
             zcbr_group.add(local_sample_dots)
 
         if first_added_anims:
@@ -424,7 +424,7 @@ class ExampleNumberlineTransformationScene(NumberlineTransformationScene):
         sample_dots = self.get_sample_dots()
         local_sample_dots = self.get_local_sample_dots(x)
 
-        self.play(LaggedStart(GrowFromCenter, sample_dots))
+        self.play(OldLaggedStart(GrowFromCenter, sample_dots))
         self.zoom_in_on_input(
             x,
             local_sample_dots=local_sample_dots,
@@ -461,7 +461,7 @@ class WriteOpeningWords(Scene):
         word_wait = 2 * letter_wait
         comma_wait = 5 * letter_wait
         for word in words:
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 FadeIn, word,
                 run_time=len(word) * letter_wait,
                 lag_ratio=1.5 / len(word)
@@ -836,7 +836,7 @@ class GraphicalIntuitions(GraphScene):
         )
         self.play(FadeIn(integral_text))
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 GrowFromEdge, rects,
                 lambda r: (r, DOWN)
             ),
@@ -858,7 +858,7 @@ class GraphicalIntuitions(GraphScene):
             word.add_background_rectangle()
         words.arrange(DOWN)
         words.to_edge(UP)
-        return LaggedStart(
+        return OldLaggedStart(
             FadeIn, words,
             rate_func=there_and_back,
             run_time=len(words) - 1,
@@ -1008,8 +1008,8 @@ class MoreTopics(Scene):
 
         self.add(calculus)
         self.play(
-            LaggedStart(ShowCreation, lines),
-            LaggedStart(Write, others),
+            OldLaggedStart(ShowCreation, lines),
+            OldLaggedStart(Write, others),
         )
         self.wait()
 
@@ -1362,12 +1362,12 @@ class IntroduceTransformationView(NumberlineTransformationScene):
             sd.save_state()
             sd.scale(2)
             sd.fade(1)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, sample_dots,
             lambda sd: (sd.restore,),
             run_time=2
         ))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             GrowArrow, arrows,
             run_time=6,
             lag_ratio=0.3,
@@ -1378,7 +1378,7 @@ class IntroduceTransformationView(NumberlineTransformationScene):
             run_time=3
         )
         self.wait()
-        self.play(LaggedStart(FadeOut, arrows, run_time=1))
+        self.play(OldLaggedStart(FadeOut, arrows, run_time=1))
 
         self.sample_dots = sample_dots
         self.sample_dot_ghosts = sample_dot_ghosts
@@ -1539,8 +1539,8 @@ class TalkThroughXSquaredExample(IntroduceTransformationView):
         sample_dot_ghosts = sample_dots.copy().fade(0.5)
 
         self.play(
-            LaggedStart(DrawBorderThenFill, sample_dots),
-            LaggedStart(FadeOut, int_arrows),
+            OldLaggedStart(DrawBorderThenFill, sample_dots),
+            OldLaggedStart(FadeOut, int_arrows),
         )
         self.remove(int_dot_ghosts)
         self.add(sample_dot_ghosts)
@@ -1952,8 +1952,8 @@ class XSquaredForNegativeInput(TalkThroughXSquaredExample):
         )
         sample_dots.set_fill(opacity=0.8)
 
-        self.play(LaggedStart(DrawBorderThenFill, sample_dots))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(DrawBorderThenFill, sample_dots))
+        self.play(OldLaggedStart(
             ApplyFunction, sample_dots[len(sample_dots) / 2:0:-1],
             lambda mob: (
                 lambda m: m.scale(2).shift(SMALL_BUFF * UP).set_color(PINK),
@@ -2062,7 +2062,7 @@ class IntroduceContinuedFractionPuzzle(PiCreatureScene):
         group.to_corner(UR)
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 Write, frac,
                 run_time=15,
                 lag_ratio=0.15,
@@ -2370,7 +2370,7 @@ class ThinkAboutWithRepeatedApplication(IntroduceContinuedFractionPuzzle):
             morty.change, "confused",
             friend.change, "confused",
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreationThenDestruction, plus_rects,
             run_time=2,
             lag_ratio=0.35,
@@ -2398,9 +2398,9 @@ class ThinkAboutWithRepeatedApplication(IntroduceContinuedFractionPuzzle):
         question.next_to(arrow, RIGHT)
 
         self.play(
-            LaggedStart(FadeIn, question, run_time=1),
+            OldLaggedStart(FadeIn, question, run_time=1),
             GrowArrow(arrow),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, frac,
                 lambda m: (m.set_color, RED),
                 rate_func=there_and_back,
@@ -2657,7 +2657,7 @@ class ShowRepeatedApplication(Scene):
         self.wait()
 
         self.play(GrowFromEdge(line[5], LEFT))
-        self.play(LaggedStart(GrowFromCenter, line[6]))
+        self.play(OldLaggedStart(GrowFromCenter, line[6]))
         self.wait()
 
         self.play(FadeIn(line[7]))
@@ -2954,7 +2954,7 @@ class AnalyzeFunctionWithTransformations(NumberlineTransformationScene):
         sample_dots.set_stroke(BLACK, 0.5)
         sample_points = list(map(Mobject.get_center, sample_dots))
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInAndShiftFromDirection, sample_dots,
             lambda m: (m, UP)
         ))
@@ -3011,9 +3011,9 @@ class AnalyzeFunctionWithTransformations(NumberlineTransformationScene):
         one_plus_rect = BackgroundRectangle(one_plus)
         one_plus_rect.set_fill(BLACK, opacity=0.8)
 
-        self.play(LaggedStart(GrowArrow, arrows))
+        self.play(OldLaggedStart(GrowArrow, arrows))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, arrows,
             lambda a: (a.scale, 0.7),
             rate_func=there_and_back,
@@ -3067,7 +3067,7 @@ class AnalyzeFunctionWithTransformations(NumberlineTransformationScene):
             return arrow
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ApplyFunction, self.all_arrows,
                 lambda a: (fade_arrow, a)
             ),
@@ -3242,7 +3242,7 @@ class StabilityAndInstability(AnalyzeFunctionWithTransformations):
             arrows = VGroup(*[a for a in self.all_arrows if get_norm(a.get_start() - point) < 0.75]).copy()
             arrows.set_fill(PINK, 1)
             arrows.set_stroke(PINK, 3)
-            arrows.second_anim = LaggedStart(
+            arrows.second_anim = OldLaggedStart(
                 ApplyMethod, arrows,
                 lambda m: (m.set_color, YELLOW),
                 rate_func=there_and_back_with_pause,
@@ -3312,7 +3312,7 @@ class StabilityAndInstability(AnalyzeFunctionWithTransformations):
 
         for deriv_label, dot_group in zip(deriv_labels, dot_groups):
             self.play(FadeInFromDown(deriv_label))
-            self.play(LaggedStart(GrowFromCenter, dot_group))
+            self.play(OldLaggedStart(GrowFromCenter, dot_group))
             self.play(*list(map(MoveToTarget, dot_group)), run_time=2)
             self.wait()
 
@@ -3336,7 +3336,7 @@ class StaticAlgebraicObject(Scene):
         polynomial.move_to(title)
 
         self.add(title)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             GrowFromCenter, frac,
             lag_ratio=0.1,
             run_time=3
@@ -3431,7 +3431,7 @@ class TopicsAfterSingleVariable(PiCreatureScene, MoreTopics):
             creature.target.change(mode, self.other_topics)
         creatures.fade(1)
 
-        self.play(LaggedStart(MoveToTarget, creatures))
+        self.play(OldLaggedStart(MoveToTarget, creatures))
         self.wait(2)
 
     def zero_in_on_complex_analysis(self):
@@ -3443,8 +3443,8 @@ class TopicsAfterSingleVariable(PiCreatureScene, MoreTopics):
             complex_analysis.scale, 1.25,
             complex_analysis.center,
             complex_analysis.to_edge, UP,
-            LaggedStart(FadeOut, self.other_topics),
-            LaggedStart(FadeOut, self.lines),
+            OldLaggedStart(FadeOut, self.other_topics),
+            OldLaggedStart(FadeOut, self.lines),
             FadeOut(self.calculus),
             *[
                 ApplyMethod(creature.change, "pondering")
@@ -3565,7 +3565,7 @@ class PrinciplesOverlay(PiCreatureScene):
         self.wait(4)
         self.play(FadeInFromDown(q_marks[0]))
         self.wait(2)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInFromDown, q_marks[1:],
             run_time=3
         ))
@@ -3598,7 +3598,7 @@ class ManyInfiniteExpressions(Scene):
         power_tower.set_color_by_gradient(BLUE, GREEN)
 
         self.play(*[
-            LaggedStart(
+            OldLaggedStart(
                 GrowFromCenter, group,
                 lag_ratio=0.1,
                 run_time=8,
diff --git a/old_projects/basel/basel.py b/old_projects/basel/basel.py
index d0271542..954309cb 100644
--- a/old_projects/basel/basel.py
+++ b/old_projects/basel/basel.py
@@ -4044,11 +4044,11 @@ class FinalSumManipulationScene(PiCreatureScene):
             full_ambient_lights.add(ls.ambient_light)
 
         self.play(
-            LaggedStart(FadeIn, full_lighthouses, lag_ratio = 0.2, run_time = 3),
+            OldLaggedStart(FadeIn, full_lighthouses, lag_ratio = 0.2, run_time = 3),
         )
 
         self.play(
-            LaggedStart(SwitchOn, full_ambient_lights, lag_ratio = 0.2, run_time = 3)
+            OldLaggedStart(SwitchOn, full_ambient_lights, lag_ratio = 0.2, run_time = 3)
         )
 
         # for ls in full_lights.submobjects:
@@ -4397,7 +4397,7 @@ class InfiniteCircleScene(PiCreatureScene):
 
         self.wait()
         self.play(
-            LaggedStart(FadeIn,infsum,lag_ratio = 0.2)
+            OldLaggedStart(FadeIn,infsum,lag_ratio = 0.2)
         )
         self.wait()
 
diff --git a/old_projects/basel/basel2.py b/old_projects/basel/basel2.py
index 9d58dac2..e2b39df8 100644
--- a/old_projects/basel/basel2.py
+++ b/old_projects/basel/basel2.py
@@ -828,8 +828,8 @@ class MathematicalWebOfConnections(PiCreatureScene):
 
         self.play(
             Write(title),
-            LaggedStart(ShowCreation, edges, run_time = 3),
-            LaggedStart(GrowFromCenter, dots, run_time = 3)
+            OldLaggedStart(ShowCreation, edges, run_time = 3),
+            OldLaggedStart(GrowFromCenter, dots, run_time = 3)
         )
         self.play(path_dots[0].set_color, RED)
         for dot, edge in zip(path_dots[1:], path_edges):
@@ -956,12 +956,12 @@ class FirstLighthouseScene(PiCreatureScene):
         self.play(morty.restore)
         self.play(
             morty.change, "pondering",
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, lighthouses,
                 run_time = 1
             )
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             SwitchOn, VGroup(*[
                 ls.ambient_light
                 for ls in light_sources
@@ -1043,7 +1043,7 @@ class FirstLighthouseScene(PiCreatureScene):
         )
 
         # First lighthouse has apparent reading
-        self.play(LaggedStart(FadeOut, light_sources[1:]))
+        self.play(OldLaggedStart(FadeOut, light_sources[1:]))
         self.wait()
         self.play(
             triangle_anim,
@@ -1088,11 +1088,11 @@ class FirstLighthouseScene(PiCreatureScene):
 
         #Switch them all on
         self.play(
-            LaggedStart(FadeIn, lighthouses[1:]),
+            OldLaggedStart(FadeIn, lighthouses[1:]),
             morty.change, "hooray",
         )
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 SwitchOn, VGroup(*[
                     ls.ambient_light
                     for ls in light_sources[1:]
@@ -1121,7 +1121,7 @@ class FirstLighthouseScene(PiCreatureScene):
         morty = self.pi_creature
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 Rotate, light_sources,
                 lambda m : (m, (2*random.random()-1)*90*DEGREES),
                 about_point = origin, 
@@ -1838,7 +1838,7 @@ class InverseSquareLaw(ThreeDScene):
             run_time = 2,
         )
         self.begin_ambient_camera_rotation(rate = -0.01)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, screen_copy_groups[2],
             lambda m : (m.set_color, RED),
             run_time = 5,
@@ -1899,7 +1899,7 @@ class OtherInstanceOfInverseSquareLaw(Scene):
             return Broadcast(dot, big_radius = 5, run_time = 5)
 
         self.play(
-            LaggedStart(FadeIn, items, run_time = 4, lag_ratio = 0.7),
+            OldLaggedStart(FadeIn, items, run_time = 4, lag_ratio = 0.7),
             Succession(*[
                 get_broadcast()
                 for x in range(2)
@@ -2276,7 +2276,7 @@ class TwoLightSourcesScene(ManipulateLightsourceSetups):
         self.play(FadeIn(lsC))
         self.play(
             Write(identical_lighthouses_words),
-            LaggedStart(GrowArrow, identical_lighthouses_arrows)
+            OldLaggedStart(GrowArrow, identical_lighthouses_arrows)
         )
         self.wait()
         self.play(*list(map(FadeOut, [
@@ -2337,7 +2337,7 @@ class MathologerVideoWrapper(Scene):
 
         self.play(
             logo.shift, FRAME_WIDTH*LEFT,
-            LaggedStart(FadeIn, title),
+            OldLaggedStart(FadeIn, title),
             run_time = 2
         )
         self.play(ShowCreation(screen))
@@ -2646,8 +2646,8 @@ class IPTScene(TwoLightSourcesScene, ZoomedScene):
         self.wait()
         spotlights_update_anim.update(0)
         self.play(
-            LaggedStart(FadeIn, spotlight_a),
-            LaggedStart(FadeIn, spotlight_b),
+            OldLaggedStart(FadeIn, spotlight_a),
+            OldLaggedStart(FadeIn, spotlight_b),
             Animation(screen_arrow),
         )
         self.add(spotlights_update_anim)
@@ -4043,11 +4043,11 @@ class FinalSumManipulationScene(PiCreatureScene):
             full_ambient_lights.add(ls.ambient_light)
 
         self.play(
-            LaggedStart(FadeIn, full_lighthouses, lag_ratio = 0.2, run_time = 3),
+            OldLaggedStart(FadeIn, full_lighthouses, lag_ratio = 0.2, run_time = 3),
         )
 
         self.play(
-            LaggedStart(SwitchOn, full_ambient_lights, lag_ratio = 0.2, run_time = 3)
+            OldLaggedStart(SwitchOn, full_ambient_lights, lag_ratio = 0.2, run_time = 3)
         )
 
         # for ls in full_lights.submobjects:
@@ -4333,7 +4333,7 @@ class InfiniteCircleScene(PiCreatureScene):
 
         self.wait()
         self.play(
-            LaggedStart(FadeIn,infsum,lag_ratio = 0.2)
+            OldLaggedStart(FadeIn,infsum,lag_ratio = 0.2)
         )
         self.wait()
 
@@ -4404,7 +4404,7 @@ class Credits(Scene):
         patreon_logo.to_edge(UP)
 
         for credit in credits:
-            self.play(LaggedStart(FadeIn, credit[0]))
+            self.play(OldLaggedStart(FadeIn, credit[0]))
             self.play(FadeIn(credit[1]))
         self.wait()
         self.play(
diff --git a/old_projects/bell.py b/old_projects/bell.py
index 3197d684..d49bfe9d 100644
--- a/old_projects/bell.py
+++ b/old_projects/bell.py
@@ -887,7 +887,7 @@ class ShowVariousFilterPairsFrom0To45(ShowVariousFilterPairs):
         for cos, rect in zip(cosines, rects[1:]):
             cos.next_to(rect, OUT, SMALL_BUFF)
 
-        self.play(LaggedStart(ShowCreation, rects))
+        self.play(OldLaggedStart(ShowCreation, rects))
         self.wait()
         self.play(*list(map(Write, cosines)), run_time = 2)
         self.wait()
@@ -1926,7 +1926,7 @@ class VennDiagramProofByContradiction(Scene):
             mover.generate_target()
             mover.target.shift(1.2*UP + 0.6*LEFT)
             mover.target.set_stroke(WHITE)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             MoveToTarget, movers,
             path_arc = np.pi,
             lag_ratio = 0.3
diff --git a/old_projects/borsuk_addition.py b/old_projects/borsuk_addition.py
index dfb8d806..6d01fb6c 100644
--- a/old_projects/borsuk_addition.py
+++ b/old_projects/borsuk_addition.py
@@ -126,7 +126,7 @@ class UnexpectedConnection(Scene):
         self.add(circle, radius, center_dot, decimal, arc)
         self.play(
             Rotate(radius, PI - 1e-7, about_point=center),
-            LaggedStart(FadeInFromDown, primes),
+            OldLaggedStart(FadeInFromDown, primes),
             run_time=4
         )
         self.remove(decimal)
@@ -172,8 +172,8 @@ class MapOfVideo(MovingCameraScene):
             Arrow(images[3], images[4], buff=SMALL_BUFF),
         )
 
-        self.play(LaggedStart(FadeInFromDown, images, run_time=4))
-        self.play(LaggedStart(GrowArrow, arrows))
+        self.play(OldLaggedStart(FadeInFromDown, images, run_time=4))
+        self.play(OldLaggedStart(GrowArrow, arrows))
         self.wait()
         group = Group(images, arrows)
         for image in images:
@@ -240,7 +240,7 @@ class MathIsDeep(PiCreatureScene):
         # num_mobs[1].add_subpath(num_mobs[1].points)
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 FadeInFromLarge, words,
                 scale_factor=1.5,
                 run_time=0.6,
@@ -258,7 +258,7 @@ class MathIsDeep(PiCreatureScene):
             self.pi_creature.change, "thinking",
             *map(GrowArrow, low_arrows),
         )
-        self.play(LaggedStart(ShowCreationThenDestruction, n_sum_border))
+        self.play(OldLaggedStart(ShowCreationThenDestruction, n_sum_border))
         self.play(Blink(self.pi_creature))
         self.wait()
 
@@ -358,15 +358,15 @@ class TopologyWordBreak(Scene):
         genus_labels.shift(SMALL_BUFF * UP)
 
         self.play(Write(word))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, word,
             lambda m: (m.set_color, m.target_color),
             run_time=1
         ))
         self.play(
-            LaggedStart(MoveToTarget, word),
-            LaggedStart(FadeIn, signs),
-            LaggedStart(FadeInFromDown, genus_labels),
+            OldLaggedStart(MoveToTarget, word),
+            OldLaggedStart(FadeIn, signs),
+            OldLaggedStart(FadeInFromDown, genus_labels),
         )
         self.wait(3)
 
@@ -533,7 +533,7 @@ class FunctionGInSymbols(Scene):
         self.wait()
         self.play(neg_g_of_p.restore)
         rects = VGroup(*map(SurroundingRectangle, [f_of_p, f_of_neg_p]))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreationThenDestruction, rects,
             lag_ratio=0.8
         ))
@@ -1128,12 +1128,12 @@ class DivisionOfUnity(Scene):
             brace.add(label)
 
         self.add(line, lower_brace)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreation, v_lines[1:3],
             lag_ratio=0.8,
             run_time=1
         ))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             GrowFromCenter, upper_braces
         ))
         self.wait()
diff --git a/old_projects/clacks/question.py b/old_projects/clacks/question.py
index 300813ae..cd7dafca 100644
--- a/old_projects/clacks/question.py
+++ b/old_projects/clacks/question.py
@@ -446,7 +446,7 @@ class MathAndPhysicsConspiring(Scene):
         to_fade = VGroup(math_title, *math_stuffs, physics_title)
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 FadeInFromDown, to_fade,
                 lag_ratio=0.7,
                 run_time=3,
@@ -605,7 +605,7 @@ class TwoBlocksLabel(Scene):
         arrows.set_color(RED)
         self.play(
             Write(label),
-            LaggedStart(GrowArrow, arrows, lag_ratio=0.7),
+            OldLaggedStart(GrowArrow, arrows, lag_ratio=0.7),
             run_time=1
         )
         self.wait()
@@ -928,7 +928,7 @@ class PiComputingAlgorithmsAxes(Scene):
             method.shift_onto_screen()
             algorithms.add(VGroup(method, cross))
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInFromDown, algorithms,
             run_time=4,
             lag_ratio=0.4,
@@ -1238,7 +1238,7 @@ class CompareToGalacticMass(Scene):
         self.play(
             Write(equals),
             Write(words),
-            LaggedStart(
+            OldLaggedStart(
                 Restore, black_holes,
                 run_time=3
             )
@@ -1374,7 +1374,7 @@ class CompareAlgorithmToPhysics(PiCreatureScene):
                 target_mode="pondering",
                 look_at_arg=left_rect,
             ),
-            LaggedStart(
+            OldLaggedStart(
                 FadeInFrom, digits,
                 lambda m: (m, LEFT),
                 run_time=5,
@@ -1491,7 +1491,7 @@ class NextVideo(Scene):
         self.play(Write(dots))
         self.wait()
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 FadeInFrom, mid_words,
                 lambda m: (m, UP),
                 lag_ratio=0.8,
@@ -1507,11 +1507,11 @@ class NextVideo(Scene):
             ShowCreation(speech_bubble),
             Write(speech_bubble.content),
             randy.change, "maybe", friends[0].eyes,
-            LaggedStart(FadeInFromDown, friends),
+            OldLaggedStart(FadeInFromDown, friends),
             videos.space_out_submobjects, 1.6,
         )
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, friends,
                 lambda m: (m.change, "pondering"),
                 run_time=1,
diff --git a/old_projects/clacks/solution1.py b/old_projects/clacks/solution1.py
index 2ae629bf..d3be24de 100644
--- a/old_projects/clacks/solution1.py
+++ b/old_projects/clacks/solution1.py
@@ -363,7 +363,7 @@ class AskAboutFindingNewVelocities(Scene):
             ))
 
         for group in label_groups:
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 ShowCreation, group.rects,
                 lag_ratio=0.8,
                 run_time=1,
@@ -693,7 +693,7 @@ class IntroduceVelocityPhaseSpace(AskAboutFindingNewVelocities):
             FadeOut(equations[1].highlighted_copy),
             run_time=0.75,
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Indicate, v_terms,
             lag_ratio=0.75,
             rate_func=there_and_back,
@@ -1475,7 +1475,7 @@ class AnalyzeCircleGeometry(CircleDiagramFromSlidingBlocks, MovingCameraScene):
             run_time=2,
         ))
         self.wait()
-        self.play(LaggedStart(MoveToTarget, movers))
+        self.play(OldLaggedStart(MoveToTarget, movers))
         self.wait()
 
         self.arcs_equation = movers
@@ -1526,8 +1526,8 @@ class AnalyzeCircleGeometry(CircleDiagramFromSlidingBlocks, MovingCameraScene):
             "run_time": 3,
         }
         self.play(
-            LaggedStart(MoveToTarget, all_arcs, **kwargs),
-            LaggedStart(MoveToTarget, arc_counts, **kwargs),
+            OldLaggedStart(MoveToTarget, all_arcs, **kwargs),
+            OldLaggedStart(MoveToTarget, arc_counts, **kwargs),
         )
 
         self.arc_counts = arc_counts
@@ -1582,7 +1582,7 @@ class AnalyzeCircleGeometry(CircleDiagramFromSlidingBlocks, MovingCameraScene):
         to_fade = VGroup(arc_counts, arcs, lines_to_fade)
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 FadeOut, VGroup(*to_fade.family_members_with_points())
             )
         )
@@ -1631,7 +1631,7 @@ class AnalyzeCircleGeometry(CircleDiagramFromSlidingBlocks, MovingCameraScene):
             FadeOut(self.center_lines_group),
             FadeOut(self.three_dots),
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyFunction, every_other_line,
             lambda line: (
                 lambda l: l.scale(10 / l.get_length()).set_stroke(BLUE, 3),
@@ -2224,7 +2224,7 @@ class ComputeThetaFor1e4(AnalyzeCircleGeometry):
         # Swap last two
         sm = movers.submobjects
         sm[-1], sm[-2] = sm[-2], sm[-1]
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Transform, movers[:-1],
             lambda m: (m, m.target),
             lag_ratio=1,
@@ -2272,8 +2272,8 @@ class ThetaChart(Scene):
         lines.set_stroke(WHITE, 1)
 
         self.play(
-            LaggedStart(FadeInFromDown, titles),
-            LaggedStart(ShowCreation, lines, lag_ratio=0.8),
+            OldLaggedStart(FadeInFromDown, titles),
+            OldLaggedStart(ShowCreation, lines, lag_ratio=0.8),
         )
 
         self.h_line = h_line
@@ -2316,11 +2316,11 @@ class ThetaChart(Scene):
             h_lines.add(h_line)
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 FadeInFromDown,
                 VGroup(*[em[:2] for em in entry_mobs]),
             ),
-            LaggedStart(ShowCreation, h_lines[1:]),
+            OldLaggedStart(ShowCreation, h_lines[1:]),
             lag_ratio=0.1,
             run_time=5,
         )
@@ -2331,7 +2331,7 @@ class ThetaChart(Scene):
     def show_values(self):
         values = VGroup(*[em[2] for em in self.entry_mobs])
         for value in values:
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 FadeIn, value,
                 lag_ratio=0.1,
                 run_time=0.5
@@ -2923,7 +2923,7 @@ class ConservationLawSummary(Scene):
         self.add(energy_group, momentum_group)
         self.wait()
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ShowCreationThenDestruction,
                 red_energy_word
             ),
diff --git a/old_projects/clacks/solution2/mirror_scenes.py b/old_projects/clacks/solution2/mirror_scenes.py
index 5a0a9cf5..4bfbe36c 100644
--- a/old_projects/clacks/solution2/mirror_scenes.py
+++ b/old_projects/clacks/solution2/mirror_scenes.py
@@ -563,7 +563,7 @@ class ReflectWorldThroughMirrorNew(MirrorScene):
             mob.become(mob.pre_world)
             mob.fade(1)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Restore, new_worlds,
             lag_ratio=0.4,
             run_time=3
@@ -580,7 +580,7 @@ class ReflectWorldThroughMirrorNew(MirrorScene):
     def blink_all_randys(self):
         randys = self.randys = VGroup(self.randy)
         randys.add(*[rw[-1] for rw in self.reflected_worlds])
-        self.play(LaggedStart(Blink, randys))
+        self.play(OldLaggedStart(Blink, randys))
 
     def add_randy_updates(self):
         # Makes it run slower, but it's fun!
@@ -911,7 +911,7 @@ class MirrorAndWiresOverlay(MirrorScene):
         self.play(
             FadeIn(diagram.rect),
             ShowCreation(diagram.mirror),
-            LaggedStart(ShowCreation, diagram.wires),
+            OldLaggedStart(ShowCreation, diagram.wires),
             run_time=1
         )
         self.remove(diagram)
diff --git a/old_projects/clacks/solution2/position_phase_space.py b/old_projects/clacks/solution2/position_phase_space.py
index 650b6e89..5cc15ca9 100644
--- a/old_projects/clacks/solution2/position_phase_space.py
+++ b/old_projects/clacks/solution2/position_phase_space.py
@@ -844,7 +844,7 @@ class EqualMassCase(PositionPhaseSpaceScene):
 
     def show_same_mass(self):
         blocks = self.blocks
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Indicate, blocks,
             lag_ratio=0.8,
             run_time=1,
@@ -1468,7 +1468,7 @@ class IntroduceVelocityVector(PositionPhaseSpaceScene, MovingCameraScene):
         ps_vect = self.ps_velocity_vector
         block_vectors = self.get_block_velocity_vectors(ps_vect)
 
-        self.play(LaggedStart(GrowArrow, block_vectors))
+        self.play(OldLaggedStart(GrowArrow, block_vectors))
         self.play(Rotating(
             ps_vect,
             angle=TAU,
@@ -1811,7 +1811,7 @@ class ShowMomentumConservation(IntroduceVelocityVector):
         self.block_vectors = self.get_block_velocity_vectors(self.ps_vect)
         self.play(
             GrowArrow(self.ps_vect),
-            LaggedStart(GrowArrow, self.block_vectors, run_time=1),
+            OldLaggedStart(GrowArrow, self.block_vectors, run_time=1),
         )
         self.add(self.ps_vect, self.block_vectors)
 
@@ -1867,7 +1867,7 @@ class ShowMomentumConservation(IntroduceVelocityVector):
         for eq, new_eq in zip(eqs_targets, new_eqs):
             new_eq.move_to(eq)
 
-        self.play(LaggedStart(MoveToTarget, eqs, lag_ratio=0.7))
+        self.play(OldLaggedStart(MoveToTarget, eqs, lag_ratio=0.7))
         self.play(*[
             Transform(
                 eq, new_eq,
@@ -1927,7 +1927,7 @@ class ShowMomentumConservation(IntroduceVelocityVector):
         for mover, part in zip(movers, final_eq):
             mover.target = part
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 MoveToTarget, movers,
                 path_arc=30 * DEGREES,
                 lag_ratio=0.9
@@ -2292,7 +2292,7 @@ class ShowMomentumConservation(IntroduceVelocityVector):
         arcs = VGroup(arc1, arc2)
 
         self.slide(0.5)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInFromLarge, arcs,
             lag_ratio=0.75,
         ))
diff --git a/old_projects/clacks/solution2/simple_scenes.py b/old_projects/clacks/solution2/simple_scenes.py
index 443a9d08..de19b8cd 100644
--- a/old_projects/clacks/solution2/simple_scenes.py
+++ b/old_projects/clacks/solution2/simple_scenes.py
@@ -575,21 +575,21 @@ class TwoSolutionsWrapper(WrapperScene):
 
         self.add(big_rect, title, pis)
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ShowCreation, screen_rects.copy().set_fill(opacity=0),
                 lag_ratio=0.8
             ),
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, screen_rects,
                 lag_ratio=0.8
             ),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, pis,
                 lambda pi: (pi.change, "pondering", screen_rects[0])
             ),
         )
         self.play(Blink(random.choice(pis)))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, pis,
             lambda pi: (pi.change, "thinking", screen_rects[1])
         ))
diff --git a/old_projects/crypto.py b/old_projects/crypto.py
index c2f2bb23..81c16056 100644
--- a/old_projects/crypto.py
+++ b/old_projects/crypto.py
@@ -120,7 +120,7 @@ class AskQuestion(Scene):
             n_chars = len(word.strip())
             n_spaces = len(word) - n_chars
             self.play(
-                LaggedStart(FadeIn, part),
+                OldLaggedStart(FadeIn, part),
                 run_time = self.time_per_char * len(word),
                 rate_func = squish_rate_func(smooth, 0, 0.5)
             )
@@ -299,7 +299,7 @@ class ListRecentCurrencies(Scene):
             self.play(*anims)
         dots = TexMobject("\\vdots")
         dots.next_to(logos, DOWN)
-        self.play(LaggedStart(FadeIn, dots, run_time = 1))
+        self.play(OldLaggedStart(FadeIn, dots, run_time = 1))
         self.wait()
 
 class Hype(TeacherStudentsScene):
@@ -503,7 +503,7 @@ class LedgerScene(PiCreatureScene):
 
     def animate_payment_addition(self, *args, **kwargs):
         line = self.add_payment_line_to_ledger(*args, **kwargs)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, 
             VGroup(*it.chain(*line)),
             run_time = 1
@@ -797,7 +797,7 @@ class IntroduceLedgerSystem(LedgerScene):
             FadeIn(tally_up)
         )
         self.play(
-            LaggedStart(FadeIn, results),
+            OldLaggedStart(FadeIn, results),
             *[
                 ApplyMethod(pi.change, "happy")
                 for pi in creditors
@@ -845,7 +845,7 @@ class InitialProtocol(Scene):
 
         for item in items:
             self.wait()
-            self.play(LaggedStart(FadeIn, item))
+            self.play(OldLaggedStart(FadeIn, item))
         self.wait(2)
 
     def get_new_item(self, item_string):
@@ -941,7 +941,7 @@ class IntroduceSignatures(LedgerScene):
             self.add_payment_line_to_ledger(*payment)
             for payment in self.payments
         ])
-        self.play(LaggedStart(FadeIn, transactions))
+        self.play(OldLaggedStart(FadeIn, transactions))
         self.wait()
 
     def add_signatures(self):
@@ -986,7 +986,7 @@ class AskHowDigitalSignaturesArePossible(TeacherStudentsScene):
         )
         self.change_student_modes("pondering", "confused", "erm")
         self.play(Write(signature))
-        self.play(LaggedStart(FadeIn, bits, run_time = 1))
+        self.play(OldLaggedStart(FadeIn, bits, run_time = 1))
         self.wait()
         self.play(ReplacementTransform(
             bits.copy(), bits_copy,
@@ -1099,7 +1099,7 @@ class DescribeDigitalSignatures(LedgerScene):
         ])
 
         self.play(ShowCreation(rects))
-        self.play(LaggedStart(DrawBorderThenFill, locks))
+        self.play(OldLaggedStart(DrawBorderThenFill, locks))
         self.wait()
 
         self.private_key_rects = rects
@@ -1142,7 +1142,7 @@ class DescribeDigitalSignatures(LedgerScene):
 
         self.play(
             FadeOut(self.title),
-            LaggedStart(FadeIn, documents, run_time = 1)
+            OldLaggedStart(FadeIn, documents, run_time = 1)
         )
         self.play(Write(signatures))
         self.wait()
@@ -1460,7 +1460,7 @@ class IncludeTransactionNumber(LedgerScene):
         copies.next_to(line, DOWN, buff = MED_SMALL_BUFF)
 
         self.play(
-            LaggedStart(FadeIn, copies, run_time = 3),
+            OldLaggedStart(FadeIn, copies, run_time = 3),
             self.bob.change, "conniving",
         )
         self.play(self.alice.change, "angry")
@@ -1546,7 +1546,7 @@ class CharlieRacksUpDebt(SignedLedgerScene):
             for payment in self.payments
         ])
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, lines, 
             run_time = 3,
             lag_ratio = 0.25
@@ -1633,7 +1633,7 @@ class LedgerWithInitialBuyIn(SignedLedgerScene):
             money.move_to(corner)
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, moneys,
                 lambda m : (m.restore,)
             ),
@@ -1665,7 +1665,7 @@ class LedgerWithInitialBuyIn(SignedLedgerScene):
         lines[-1].add(line)
 
         self.play(
-            LaggedStart(FadeIn, lines),
+            OldLaggedStart(FadeIn, lines),
             *[
                 ApplyMethod(pi.change, "thinking", self.ledger)
                 for pi in self.pi_creatures
@@ -1757,8 +1757,8 @@ class LedgerWithInitialBuyIn(SignedLedgerScene):
             FadeIn(balance)
         )
         self.play(
-            LaggedStart(FadeIn, lines, run_time = 3),
-            LaggedStart(ShowCreation, arrows, run_time = 3),
+            OldLaggedStart(FadeIn, lines, run_time = 3),
+            OldLaggedStart(ShowCreation, arrows, run_time = 3),
         )
         self.wait()
 
@@ -1852,7 +1852,7 @@ class RenameToLedgerDollars(LedgerScene):
             for payment in self.payments
         ])
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, lines,
             run_time = 4,
             lag_ratio = 0.3
@@ -2126,7 +2126,7 @@ class TransitionToDistributedLedger(DistributedLedgerScene):
         ])
 
         for payment in payments:
-            self.play(LaggedStart(FadeIn, payment, run_time = 1))
+            self.play(OldLaggedStart(FadeIn, payment, run_time = 1))
             self.wait()
 
     def ask_who_controls_ledger(self):
@@ -2449,9 +2449,9 @@ class ThisIsWellIntoTheWeeds(TeacherStudentsScene):
         )
         self.change_student_modes(
             *["pondering"]*3,
-            added_anims = [LaggedStart(FadeIn, lightbulb)]
+            added_anims = [OldLaggedStart(FadeIn, lightbulb)]
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, lightbulb,
             lambda b : (b.set_color, YELLOW_A),
             rate_func = there_and_back
@@ -2515,7 +2515,7 @@ class IntroduceSHA256(Scene):
         self.remove(digest)
         for brace, text in brace_text_pairs:
             if brace is digest_brace:
-                self.play(LaggedStart(
+                self.play(OldLaggedStart(
                     FadeIn, digest,
                     run_time = 4,
                     lag_ratio = 0.05
@@ -2529,7 +2529,7 @@ class IntroduceSHA256(Scene):
         self.play(Write(looks_random))
         self.wait(2)
         for mob in digest, message:
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 ApplyMethod, mob,
                 lambda m : (m.set_color, YELLOW),
                 rate_func = there_and_back,
@@ -2736,7 +2736,7 @@ class IntroduceNonceOnTrasactions(LedgerScene):
         zeros_brace = Brace(zeros, UP)
         zeros_words = zeros_brace.get_text("30 zeros")
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, VGroup(special_word, nonce_brace, nonce)
         ))
         self.wait()
@@ -2751,20 +2751,20 @@ class IntroduceNonceOnTrasactions(LedgerScene):
             ShowCreation(arrow),
             FadeIn(sha)
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, decomposed_ledger,
             lambda m : (m.set_color, YELLOW),
             rate_func = there_and_back
         ))
         point = VectorizedPoint(sha.get_center())
         point.set_fill(opacity = 1)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Transform, decomposed_ledger.copy(),
             lambda m : (m, point),
             run_time = 1
         ))
         bit_iter = iter(digest)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ReplacementTransform, 
             VGroup(*[point.copy() for x in range(256)]),
             lambda m : (m, next(bit_iter)),
@@ -2775,7 +2775,7 @@ class IntroduceNonceOnTrasactions(LedgerScene):
             GrowFromCenter(zeros_brace),
             Write(zeros_words, run_time = 1)
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, zeros,
             lambda m : (m.set_color, YELLOW)
         ))
@@ -2974,10 +2974,10 @@ class IntroduceBlockChain(Scene):
             for block in blocks
         ])
 
-        self.play(LaggedStart(FadeIn, blocks))
+        self.play(OldLaggedStart(FadeIn, blocks))
         self.play(
             Write(blocks_word),
-            LaggedStart(
+            OldLaggedStart(
                 ShowCreation, arrows, 
                 run_time = 1,
                 lag_factor = 0.6,
@@ -2985,7 +2985,7 @@ class IntroduceBlockChain(Scene):
         )
         self.wait()
         for group in all_payments, all_proofs_of_work:
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 Indicate, group,
                 rate_func = there_and_back,
                 scale_factor = 1.1,
@@ -3045,7 +3045,7 @@ class IntroduceBlockChain(Scene):
         self.play(Write(digests))
         self.wait()
         for group in signatures, proofs_of_work:
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 Indicate, group,
                 run_time = 2,
                 rate_func = there_and_back,
@@ -3325,7 +3325,7 @@ class FromBankToDecentralizedSystem(DistributedBlockChainScene):
         cross.set_stroke(width = 10)
         group = VGroup(bank, cross)
 
-        self.play(LaggedStart(DrawBorderThenFill, bank))
+        self.play(OldLaggedStart(DrawBorderThenFill, bank))
         self.play(ShowCreation(cross))
         self.wait()
         self.play(
@@ -3349,9 +3349,9 @@ class FromBankToDecentralizedSystem(DistributedBlockChainScene):
         center_chain.scale(2)
         center_chain.center()
 
-        self.play(LaggedStart(FadeIn, creatures, run_time = 1))
+        self.play(OldLaggedStart(FadeIn, creatures, run_time = 1))
         self.play(
-            LaggedStart(FadeIn, center_chain.blocks, run_time = 1),
+            OldLaggedStart(FadeIn, center_chain.blocks, run_time = 1),
             ShowCreation(center_chain.arrows),
         )
         self.wait()
@@ -3442,7 +3442,7 @@ class IntroduceBlockCreator(DistributedBlockChainScene):
         everything.arrange(DOWN, buff = LARGE_BUFF)
         everything.to_edge(LEFT)
 
-        self.play(LaggedStart(FadeIn, everything))
+        self.play(OldLaggedStart(FadeIn, everything))
         self.pi_creatures.add(*block_creators)
         self.wait()
 
@@ -4078,7 +4078,7 @@ class DoubleSpendingAttack(DistributedBlockChainScene):
             self.charlie.change, "shruggie",
             self.you.change, "shruggie",
         )
-        self.play(LaggedStart(FadeIn, bubble))
+        self.play(OldLaggedStart(FadeIn, bubble))
         self.play(self.bob.change, "confused", words)
         self.wait(2)
 
@@ -4496,7 +4496,7 @@ class MainIdeas(Scene):
 
         self.add(title, h_line)
         for idea in ideas:
-            self.play(LaggedStart(FadeIn, idea))
+            self.play(OldLaggedStart(FadeIn, idea))
         self.wait()
 
 class VariableProofOfWork(WhenToTrustANewBlock):
@@ -4594,7 +4594,7 @@ class VariableProofOfWork(WhenToTrustANewBlock):
         everyone.to_corner(UP+LEFT)
 
         self.play(Transform(miner_block, target))
-        self.play(LaggedStart(FadeIn, copies))
+        self.play(OldLaggedStart(FadeIn, copies))
         self.change_challenge(72)
         self.wait(2)
 
@@ -4667,7 +4667,7 @@ class CompareBlockTimes(Scene):
         )
         self.wait()
         self.play(*[
-            LaggedStart(FadeIn, VGroup(*group[1:]))
+            OldLaggedStart(FadeIn, VGroup(*group[1:]))
             for group in (examples, logos)
         ])
         self.wait(2)
@@ -4720,7 +4720,7 @@ class BlockRewards(Scene):
         footnote.scale(0.5)
         footnote.to_corner(DOWN+RIGHT)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, rewards,
             run_time = 4,
             lag_ratio = 0.5
@@ -4876,7 +4876,7 @@ class ShowBitcoinBlockSize(LedgerScene):
             GrowFromCenter(brace),
             Write(limit)
         )
-        self.play(LaggedStart(FadeIn, payments))
+        self.play(OldLaggedStart(FadeIn, payments))
         self.wait()
 
         ####Visa
@@ -4899,10 +4899,10 @@ class ShowBitcoinBlockSize(LedgerScene):
         visa = VGroup(visa_logo, rates)
         visa.to_corner(UP+RIGHT)
 
-        self.play(LaggedStart(DrawBorderThenFill, visa_logo))
-        self.play(LaggedStart(FadeIn, avg_rate))
+        self.play(OldLaggedStart(DrawBorderThenFill, visa_logo))
+        self.play(OldLaggedStart(FadeIn, avg_rate))
         self.wait()
-        self.play(LaggedStart(FadeIn, max_rate))
+        self.play(OldLaggedStart(FadeIn, max_rate))
         self.wait(2)
 
 class CurrentAverageFees(Scene):
@@ -4951,7 +4951,7 @@ class TopicsNotCovered(TeacherStudentsScene):
             self.change_student_modes(
                 "confused", "thinking","pondering",
                 look_at_arg = topic,
-                added_anims = [LaggedStart(FadeIn, topic)]
+                added_anims = [OldLaggedStart(FadeIn, topic)]
             )
             self.wait()
 
@@ -5176,7 +5176,7 @@ class ProtocolLabs(PiCreatureScene):
 
         self.play(
             DrawBorderThenFill(logo[0]),
-            LaggedStart(FadeIn, logo[1]),
+            OldLaggedStart(FadeIn, logo[1]),
             morty.change, "raise_right_hand",
         )
         self.wait()
diff --git a/old_projects/dandelin.py b/old_projects/dandelin.py
index 4a2acf74..ce12c4db 100644
--- a/old_projects/dandelin.py
+++ b/old_projects/dandelin.py
@@ -27,7 +27,7 @@ class LogoGeneration(LogoGenerationTemplate):
                 run_time=3,
             ),
             AnimationGroup(*[
-                LaggedStart(
+                OldLaggedStart(
                     Restore, layer,
                     run_time=3,
                     path_arc=180 * DEGREES,
@@ -121,17 +121,17 @@ class SumOfIntegersProof(Scene):
                 square.move_to(row, LEFT)
             row.fade(1)
 
-        self.play(LaggedStart(FadeInFromDown, equation[:-1]))
+        self.play(OldLaggedStart(FadeInFromDown, equation[:-1]))
         self.wait()
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 MoveToTarget, numbers,
                 path_arc=-90 * DEGREES,
                 lag_ratio=1,
                 run_time=1
             )
         )
-        self.play(LaggedStart(Restore, rows))
+        self.play(OldLaggedStart(Restore, rows))
         self.wait()
         self.play(
             ReplacementTransform(
@@ -221,7 +221,7 @@ class MultipleDefinitionsOfAnEllipse(Scene):
             definition.saved_state = definition.copy()
             definition.saved_state.set_fill(LIGHT_GREY, 0.5)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInAndShiftFromDirection, definitions,
             lambda m: (m, RIGHT),
             run_time=4
@@ -281,7 +281,7 @@ class StretchACircle(Scene):
                 plane_circle_group.stretch, 2, 0,
                 run_time=2,
             ),
-            LaggedStart(
+            OldLaggedStart(
                 GrowArrow, arrows,
                 run_time=1,
                 lag_ratio=1
@@ -367,8 +367,8 @@ class ShowArrayOfEccentricities(Scene):
 
         self.play(
             Write(name),
-            LaggedStart(GrowArrow, arrows),
-            LaggedStart(Restore, eccentricity_labels)
+            OldLaggedStart(GrowArrow, arrows),
+            OldLaggedStart(Restore, eccentricity_labels)
         )
         self.wait()
         self.play(
@@ -404,7 +404,7 @@ class ShowArrayOfEccentricities(Scene):
             [morty]
         ))
         self.play(
-            LaggedStart(FadeOutAndShiftDown, group),
+            OldLaggedStart(FadeOutAndShiftDown, group),
             circle.set_height, 5,
             circle.center,
         )
@@ -755,7 +755,7 @@ class AskWhyAreTheyTheSame(TeacherStudentsScene):
         self.play(
             FadeOutAndShift(bubble),
             FadeOutAndShift(bubble.content),
-            LaggedStart(
+            OldLaggedStart(
                 FadeOutAndShift, self.students,
                 lambda m: (m, 3 * DOWN),
             ),
@@ -787,7 +787,7 @@ class AskWhyAreTheyTheSame(TeacherStudentsScene):
         self.wait(2)
         self.play(
             baby_morty.change, "thinking",
-            LaggedStart(DrawBorderThenFill, bubble)
+            OldLaggedStart(DrawBorderThenFill, bubble)
         )
         self.play(ShowCreation(egg))
         self.wait(3)
@@ -826,7 +826,7 @@ class TriangleOfEquivalences(Scene):
         arrows[2].move_to(rects[::2])
         arrows[1:].shift(0.5 * DOWN)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, arrows,
             lag_ratio=0.7,
             run_time=3,
@@ -893,7 +893,7 @@ class TangencyAnimation(Scene):
             ring.scale(0)
             ring.saved_state.set_stroke(width=0)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Restore, rings,
             run_time=2,
             lag_ratio=0.7
@@ -1028,7 +1028,7 @@ class ShowSegmentSplit(Scene):
             brace.scale(0)
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 Restore, braces,
                 lag_ratio=0.7
             ),
@@ -1113,7 +1113,7 @@ class WriteConjecture(Scene):
             word.rotate(angle, about_point=ORIGIN)
             word.shift(line.get_center())
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInFromDown,
             VGroup(title, equation),
             lag_ratio=0.7
@@ -1220,7 +1220,7 @@ class QuickGeometryProof(Scene):
 
         everything = VGroup(*self.mobjects)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             GrowFromCenter, everything,
             lag_ratio=0.25,
             run_time=4
@@ -1278,7 +1278,7 @@ class NameDandelin(Scene):
         self.play(Write(cmon_google, run_time=1))
         self.wait()
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInFromDown, dandelions,
             lag_ratio=0.7,
             run_time=1
@@ -1446,7 +1446,7 @@ class CreativeConstruction(PiCreatureScene):
             max_radius=15.0,
             delta_r=0.025,
         )
-        return LaggedStart(
+        return OldLaggedStart(
             FadeIn, rings,
             rate_func=there_and_back,
             run_time=2,
@@ -1508,12 +1508,12 @@ class LockhartQuote(Scene):
             self.wait(0.005 * len(word)**1.5)
         self.wait(2)
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 FadeOutAndShiftDown, quote,
                 lag_ratio=0.2,
                 run_time=5,
             ),
-            LaggedStart(
+            OldLaggedStart(
                 FadeOutAndShiftDown, pictures,
                 run_time=3,
             ),
@@ -1571,7 +1571,7 @@ class ShowApollonianCircles(Scene):
         equation.next_to(circles, UP)
 
         self.add(equation)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, circles
         ))
         self.wait()
diff --git a/old_projects/div_curl.py b/old_projects/div_curl.py
index 15481911..7e0940ff 100644
--- a/old_projects/div_curl.py
+++ b/old_projects/div_curl.py
@@ -492,7 +492,7 @@ class Introduction(MovingCameraScene):
 
         self.add(div_vector_field)
         self.play(
-            LaggedStart(ShowPassingFlash, stream_lines),
+            OldLaggedStart(ShowPassingFlash, stream_lines),
             FadeIn(div_title[0]),
             *list(map(GrowFromCenter, div_title[1]))
         )
@@ -576,7 +576,7 @@ class ShowWritingTrajectory(TeacherStudentsScene):
             self.get_student_changes(*["sassy"] * 3)
         )
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, dashed_path,
                 lambda m: (m.scale, 0),
                 remover=True
@@ -758,7 +758,7 @@ class CylinderModel(Scene):
             dot_update,
             exp_tex_update,
             exp_decimal_update,
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, sample_labels,
                 remover=True,
                 rate_func=there_and_back,
@@ -1000,12 +1000,12 @@ class ElectricField(CylinderModel, MovingCameraScene):
             FadeOut(self.unit_circle),
             FadeOut(self.title),
             FadeOut(self.func_label),
-            LaggedStart(GrowArrow, vector_field)
+            OldLaggedStart(GrowArrow, vector_field)
         )
         self.remove_foreground_mobjects(self.title, self.func_label)
         self.wait()
         for group, vect in (protons, UP), (electrons, DOWN):
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 ApplyMethod, group,
                 lambda m: (m.shift, (FRAME_HEIGHT + 1) * vect),
                 run_time=3,
@@ -1059,8 +1059,8 @@ class ElectricField(CylinderModel, MovingCameraScene):
             self.vector_field, unit_circle, protons, electrons
         )
         self.play(
-            LaggedStart(VFadeIn, protons),
-            LaggedStart(VFadeIn, electrons),
+            OldLaggedStart(VFadeIn, protons),
+            OldLaggedStart(VFadeIn, electrons),
         )
         self.play(
             self.camera.frame.scale, 0.7,
@@ -1341,15 +1341,15 @@ class TopicsAndConnections(Scene):
         full_rect = FullScreenFadeRectangle()
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, dots,
                 lambda d: (d.restore,)
             ),
-            LaggedStart(Write, topics),
+            OldLaggedStart(Write, topics),
         )
         self.wait()
         self.play(
-            LaggedStart(ShowCreation, connections),
+            OldLaggedStart(ShowCreation, connections),
             Animation(topics),
             Animation(dots),
         )
@@ -1428,9 +1428,9 @@ class IntroduceVectorField(Scene):
             dot.target = vector
             dots.add(dot)
 
-        self.play(LaggedStart(GrowFromCenter, dots))
+        self.play(OldLaggedStart(GrowFromCenter, dots))
         self.wait()
-        self.play(LaggedStart(MoveToTarget, dots, remover=True))
+        self.play(OldLaggedStart(MoveToTarget, dots, remover=True))
         self.add(vector_field)
         self.wait()
 
@@ -1548,12 +1548,12 @@ class ShorteningLongVectors(IntroduceVectorField):
 
         self.add(adjusted)
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             MoveToTarget, adjusted,
             run_time=3
         ))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, adjusted,
             lambda m: (m.restore,),
             run_time=3
@@ -1752,12 +1752,12 @@ class DefineDivergence(ChangingElectricField):
         vector_field = self.get_vector_field()
 
         self.play(
-            LaggedStart(GrowArrow, vector_field),
-            LaggedStart(GrowFromCenter, particles),
+            OldLaggedStart(GrowArrow, vector_field),
+            OldLaggedStart(GrowFromCenter, particles),
             run_time=4
         )
         self.wait()
-        self.play(LaggedStart(FadeOut, particles))
+        self.play(OldLaggedStart(FadeOut, particles))
 
     def show_flow(self):
         stream_lines = StreamLines(
@@ -1797,8 +1797,8 @@ class DefineDivergence(ChangingElectricField):
 
             self.play(
                 self.vector_field.set_fill, {"opacity": 0.5},
-                LaggedStart(
-                    LaggedStart, vector_circle_groups,
+                OldLaggedStart(
+                    OldLaggedStart, vector_circle_groups,
                     lambda vcg: (GrowArrow, vcg),
                 ),
             )
@@ -2160,7 +2160,7 @@ class DivergenceAsNewFunction(Scene):
         def show_flow():
             stream_lines = get_stream_lines()
             random.shuffle(stream_lines.submobjects)
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 ShowCreationThenDestruction,
                 stream_lines,
                 remover=True
@@ -2202,8 +2202,8 @@ class DivergenceAsNewFunction(Scene):
         ])
         self.add_foreground_mobjects(div_tex)
         self.play(
-            LaggedStart(GrowArrow, vector_field),
-            LaggedStart(GrowArrow, vector_ring),
+            OldLaggedStart(GrowArrow, vector_field),
+            OldLaggedStart(GrowArrow, vector_ring),
         )
         self.add(vector_ring_update)
         self.wait()
@@ -2368,7 +2368,7 @@ class IntroduceCurl(IntroduceVectorField):
             key=lambda v: v.get_length()
         )
 
-        self.play(LaggedStart(GrowArrow, vector_field))
+        self.play(OldLaggedStart(GrowArrow, vector_field))
         self.wait()
 
     def begin_flow(self):
@@ -2461,7 +2461,7 @@ class ShearCurl(IntroduceCurl):
         vector_field.submobjects.key=sort(
             key=lambda a: a.get_length()
         )
-        self.play(LaggedStart(GrowArrow, vector_field))
+        self.play(OldLaggedStart(GrowArrow, vector_field))
 
     def comment_on_relevant_region(self):
         circle = Circle(color=WHITE, radius=0.75)
@@ -2683,7 +2683,7 @@ class IllustrationUseVennDiagram(Scene):
             Animation(fluid_flow),
             Animation(ff_circle),
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, examples,
             run_time=3,
         ))
@@ -2755,7 +2755,7 @@ class MaxwellsEquations(Scene):
 
         self.add(title)
         self.add(field_definitions)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, equations,
             run_time=3,
             lag_range=0.4
@@ -2951,7 +2951,7 @@ class IllustrateGaussMagnetic(IllustrateGaussLaw):
         vector_field.submobjects.sort(
             key=lambda a: -a1.get_length()
         )
-        self.play(LaggedStart(GrowArrow, vector_field))
+        self.play(OldLaggedStart(GrowArrow, vector_field))
         self.add_foreground_mobjects(
             vector_field, *self.foreground_mobjects
         )
@@ -3033,13 +3033,13 @@ class ShowTwoPopulations(Scene):
                 Write(word, run_time=1),
             )
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, examples,
                 lambda m: (m.restore,)
             ),
-            LaggedStart(FadeOut, words),
+            OldLaggedStart(FadeOut, words),
             *[
-                LaggedStart(
+                OldLaggedStart(
                     FadeIn,
                     group[1:],
                     run_time=4,
@@ -3336,7 +3336,7 @@ class PhaseSpaceOfPopulationModel(ShowTwoPopulations, PiCreatureScene, MovingCam
             ShowCreation(rect)
         )
         self.play(
-            LaggedStart(FadeIn, equations),
+            OldLaggedStart(FadeIn, equations),
             randy.change, "confused", equations,
             VFadeIn(randy),
         )
@@ -3370,7 +3370,7 @@ class PhaseSpaceOfPopulationModel(ShowTwoPopulations, PiCreatureScene, MovingCam
         dot_vector = get_dot_vector()
 
         self.play(
-            LaggedStart(GrowArrow, vector_field),
+            OldLaggedStart(GrowArrow, vector_field),
             randy.change, "thinking", dot,
             Animation(self.differential_equation_group)
         )
@@ -4085,7 +4085,7 @@ class DivergenceTinyNudgesView(MovingCameraScene):
 
         self.play(
             Write(dot_product),
-            LaggedStart(MoveToTarget, copies)
+            OldLaggedStart(MoveToTarget, copies)
         )
         self.remove(copies)
         self.play(FadeIn(div_text))
@@ -4161,7 +4161,7 @@ class DivergenceTinyNudgesView(MovingCameraScene):
                 )
             self.play(
                 all_step_vectors.set_fill, {"opacity": 0.5},
-                LaggedStart(
+                OldLaggedStart(
                     MoveToTarget, all_diff_vectors,
                     run_time=3
                 ),
@@ -4224,7 +4224,7 @@ class DivergenceTinyNudgesView(MovingCameraScene):
                     )
                 )
             self.play(
-                LaggedStart(
+                OldLaggedStart(
                     MoveToTarget, all_diff_vectors,
                     run_time=2
                 ),
@@ -4267,7 +4267,7 @@ class DivergenceTinyNudgesView(MovingCameraScene):
             virtual_time=1,
         )
         random.shuffle(stream_lines.submobjects)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowPassingFlash,
             stream_lines,
             run_time=4,
@@ -4455,7 +4455,7 @@ class BroughtToYouBy(PiCreatureScene):
 
         self.play(
             Write(so_words[0]),
-            LaggedStart(
+            OldLaggedStart(
                 DrawBorderThenFill, so_words[1],
                 run_time=5
             ),
@@ -4477,7 +4477,7 @@ class BroughtToYouBy(PiCreatureScene):
             full_group,
             rate_func=running_start,
         ))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, patreon_logo
         ))
         self.wait()
@@ -4520,7 +4520,7 @@ class BroughtToYouBy(PiCreatureScene):
             randy.change, "thinking",
             morty.change, "thinking",
         )
-        self.play(LaggedStart(FadeOut, spiral, run_time=3))
+        self.play(OldLaggedStart(FadeOut, spiral, run_time=3))
         self.wait(3)
 
     # Helpers
@@ -4637,8 +4637,8 @@ class ThoughtsOnAds(Scene):
         )
         self.wait()
         self.play(
-            LaggedStart(FadeInFromDown, vcb),
-            LaggedStart(ShowCreation, vcb_arrows),
+            OldLaggedStart(FadeInFromDown, vcb),
+            OldLaggedStart(ShowCreation, vcb_arrows),
             ApplyMethod(
                 knob.move_to, line.get_right(), DOWN,
                 run_time=2
@@ -4754,7 +4754,7 @@ class PeopleValueGraph(GraphScene):
         self.play(Write(reach_words))
         self.wait()
         self.play(
-            LaggedStart(DrawBorderThenFill, area),
+            OldLaggedStart(DrawBorderThenFill, area),
             Animation(self.graph),
             Animation(self.axes),
             Write(area_words),
diff --git a/old_projects/domino_play.py b/old_projects/domino_play.py
index b045989b..025ff4a9 100644
--- a/old_projects/domino_play.py
+++ b/old_projects/domino_play.py
@@ -598,7 +598,7 @@ class ContrastTwoGraphs(SimpleVelocityGraph):
             target = VGroup(*it.chain(*list(zip(sg_copy.dots, sg_copy.lines))))
             for m, t in zip(mover, target):
                 m.target = t
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 MoveToTarget, mover,
                 rate_func = lambda t : 0.3*wiggle(t),
                 run_time = 3,
@@ -671,8 +671,8 @@ class ContrastTwoGraphs(SimpleVelocityGraph):
         hardwood.next_to(felt, DOWN, LARGE_BUFF)
 
         self.play(
-            LaggedStart(FadeIn, felt),
-            LaggedStart(FadeIn, hardwood),
+            OldLaggedStart(FadeIn, felt),
+            OldLaggedStart(FadeIn, hardwood),
             run_time = 1
         )
         self.wait()
@@ -693,7 +693,7 @@ class ContrastTwoGraphs(SimpleVelocityGraph):
 
         self.play(ShowCreation(rect1))
         for x in range(2):
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 ApplyMethod, dot_group1,
                 lambda m : (m.scale_in_place, 0.5),
                 rate_func = wiggle,
@@ -703,7 +703,7 @@ class ContrastTwoGraphs(SimpleVelocityGraph):
         self.wait()
         self.play(ReplacementTransform(rect1, rect2))
         for x in range(2):
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 ApplyMethod, dot_group2,
                 lambda m : (m.scale_in_place, 0.5),
                 rate_func = wiggle,
@@ -713,7 +713,7 @@ class ContrastTwoGraphs(SimpleVelocityGraph):
         self.wait()
         self.play(ReplacementTransform(rect1, rect3))
         for x in range(2):
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 ApplyMethod, dot_group3,
                 lambda m : (m.scale_in_place, 0.5),
                 rate_func = wiggle,
diff --git a/old_projects/fc1.py b/old_projects/fc1.py
index 5b0988d3..838b904b 100644
--- a/old_projects/fc1.py
+++ b/old_projects/fc1.py
@@ -28,7 +28,7 @@ class CrossingOneMillion(TeacherStudentsScene):
                 rate_func=bezier([0, 0, 0, 1, 1, 1]),
                 run_time=5,
             ),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, self.get_pi_creatures(),
                 lambda m: (m.change, "hooray", number),
                 rate_func=squish_rate_func(smooth, 0, 0.5),
@@ -172,12 +172,12 @@ class AllFeaturedCreators(MortyPiCreatureScene):
             Write(title)
         )
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, dots,
             lambda m: (m.restore,)
         ))
         self.play(
-            LaggedStart(FadeIn, rects, lag_ratio=0.7),
+            OldLaggedStart(FadeIn, rects, lag_ratio=0.7),
             morty.change, "happy"
         )
         self.add(creators, rects)
diff --git a/old_projects/for_flammy.py b/old_projects/for_flammy.py
index e08c771b..2b84b7b8 100644
--- a/old_projects/for_flammy.py
+++ b/old_projects/for_flammy.py
@@ -219,7 +219,7 @@ class SphereRings(SecondProof):
         rings.sort(lambda p: p[2])
 
         for x in range(8):
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 ApplyMethod, rings,
                 lambda m: (m.set_fill, PINK, 0.5),
                 rate_func=there_and_back,
@@ -316,7 +316,7 @@ class IntegralSymbols(Scene):
         self.wait()
         self.play(
             GrowFromCenter(int_brace),
-            LaggedStart(
+            OldLaggedStart(
                 FadeInFrom, q_marks,
                 lambda m: (m, UP),
             )
diff --git a/old_projects/fourier.py b/old_projects/fourier.py
index 711e6516..5f730fe3 100644
--- a/old_projects/fourier.py
+++ b/old_projects/fourier.py
@@ -127,7 +127,7 @@ class OtherContexts(PiCreatureScene):
         self.add(items)
         for item in items[1:]:
             self.play(
-                LaggedStart(
+                OldLaggedStart(
                     ApplyMethod, item,
                     lambda m : (m.set_fill, {"opacity" : 1}),
                 ), 
@@ -646,7 +646,7 @@ class BreakApartSum(Scene):
         rect = SurroundingRectangle(pure_graphs, color = WHITE)
         self.play(
             ShowCreation(rect),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyFunction, pure_graphs,
                 lambda g : (lambda m : m.shift(SMALL_BUFF*UP).set_color(YELLOW), g),
                 rate_func = wiggle
@@ -1124,7 +1124,7 @@ class WrapCosineGraphAroundCircle(FourierMachineScene):
         self.play(ShowCreation(graph, run_time = 2, rate_func=linear))
         self.play(
             FadeIn(words),
-            LaggedStart(FadeIn, braces),
+            OldLaggedStart(FadeIn, braces),
             *list(map(ShowCreation, v_lines))
         )
         self.wait()
@@ -1227,7 +1227,7 @@ class WrapCosineGraphAroundCircle(FourierMachineScene):
 
         self.play(ShowCreation(bps_label.rect))
         self.play(FadeOut(bps_label.rect))
-        self.play(LaggedStart(FadeIn, braces, run_time = 3))
+        self.play(OldLaggedStart(FadeIn, braces, run_time = 3))
         self.play(FadeOut(braces))
         self.play(ShowCreation(wps_label.rect))
         self.play(FadeOut(wps_label.rect))
@@ -1252,7 +1252,7 @@ class WrapCosineGraphAroundCircle(FourierMachineScene):
             )
             self.wait()
             if count == 2:
-                self.play(LaggedStart(
+                self.play(OldLaggedStart(
                     ApplyFunction, v_lines,
                     lambda mob : (
                         lambda m : m.shift(0.25*UP).set_color(YELLOW), 
@@ -1430,7 +1430,7 @@ class DrawFrequencyPlot(WrapCosineGraphAroundCircle, PiCreatureScene):
             wps_label.move_to, self.circle_plane.get_top(),
             com_label.move_to, self.circle_plane, DOWN,
         )
-        self.play(LaggedStart(FadeIn, frequency_axes))
+        self.play(OldLaggedStart(FadeIn, frequency_axes))
         self.wait()
         self.play(MoveAlongPath(
             self.center_of_mass_dot, flower_path,
@@ -1733,7 +1733,7 @@ class ShowLowerFrequency(DrawFrequencyPlot):
         self.remove(start_graph)
         self.play(
             Write(bps_label),
-            LaggedStart(FadeIn, braces),
+            OldLaggedStart(FadeIn, braces),
             *list(map(ShowCreation, v_lines)),
             run_time = 1
         )
@@ -1904,7 +1904,7 @@ class ShowLinearity(DrawFrequencyPlot):
             FadeIn(axes_copy),
             ShowCreation(high_freq_graph),
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, VGroup(high_freq_label, low_freq_label)
         ))
         self.wait()
@@ -1961,7 +1961,7 @@ class ShowLinearity(DrawFrequencyPlot):
 
         self.generate_fourier_dot_transform(fourier_graph)                
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, VGroup(
                 circle_plane, wps_label,
                 frequency_axes, x_coord_label,
@@ -2185,9 +2185,9 @@ class ShowCommutativeDiagram(ShowLinearity):
             flat_rect.target = spike_rect
             flat_rects.add(flat_rect)
 
-        self.play(LaggedStart(GrowFromCenter, flat_rects))
+        self.play(OldLaggedStart(GrowFromCenter, flat_rects))
         self.wait()
-        self.play(LaggedStart(MoveToTarget, flat_rects))
+        self.play(OldLaggedStart(MoveToTarget, flat_rects))
         self.wait()
 
         sum_spike_rects = VGroup(*[
@@ -2197,7 +2197,7 @@ class ShowCommutativeDiagram(ShowLinearity):
         self.play(ReplacementTransform(
             flat_rects, sum_spike_rects
         ))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             WiggleOutThenIn, sum_spike_rects,
             run_time = 1,
             lag_ratio = 0.7,
@@ -3046,7 +3046,7 @@ class WriteComplexExponentialExpression(DrawFrequencyPlot):
                 t_mob.shift(0.5*SMALL_BUFF*LEFT)
 
         self.play(MoveToTarget(t_mobs))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Indicate, dots[1],
             rate_func = there_and_back,
             color = TEAL,
@@ -3875,7 +3875,7 @@ class BoundsAtInfinity(SummarizeFormula):
         self.play(ReplacementTransform(
             self.get_time_interval(0, 0.01), time_interval
         ))
-        self.play(LaggedStart(ShowCreation, bound_rects))
+        self.play(OldLaggedStart(ShowCreation, bound_rects))
         self.wait()
         self.play(FadeOut(bound_rects))
         self.play(ReplacementTransform(bounds, inf_bounds))
@@ -4051,7 +4051,7 @@ class SubscribeOrBinge(PiCreatureScene):
         for video, color in zip(videos, colors):
             video.set_color(color)
         videos.move_to(binge.get_bottom(), UP)
-        video_anim = LaggedStart(
+        video_anim = OldLaggedStart(
             Succession, videos, 
             lambda v : (
                 FadeIn, v,
diff --git a/old_projects/gradient.py b/old_projects/gradient.py
index 819a6112..aa7bf41b 100644
--- a/old_projects/gradient.py
+++ b/old_projects/gradient.py
@@ -69,7 +69,7 @@ class ShowSimpleMultivariableFunction(Scene):
                 inputs,
                 many_inputs[:len(inputs)]
             ),
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn,
                 many_inputs[len(inputs):]
             ),
@@ -82,7 +82,7 @@ class ShowSimpleMultivariableFunction(Scene):
                 func_tex[0], alt_func_tex[0]
             ),
             Write(alt_func_tex[1:3]),
-            LaggedStart(FadeOutAndShiftDown, many_inputs)
+            OldLaggedStart(FadeOutAndShiftDown, many_inputs)
         )
         self.wait(3)
 
@@ -138,8 +138,8 @@ class ShowGradient(Scene):
         partials.set_fill(opacity=0)
 
         self.play(
-            LaggedStart(FadeIn, gradient),
-            LaggedStart(
+            OldLaggedStart(FadeIn, gradient),
+            OldLaggedStart(
                 FadeIn, background_rects,
                 rate_func=squish_rate_func(smooth, 0.5, 1)
             )
@@ -231,9 +231,9 @@ class TakePartialDerivatives(Scene):
         self.wait()
 
         # Label y as constant
-        self.play(LaggedStart(ShowCreation, ys.rects))
+        self.play(OldLaggedStart(ShowCreation, ys.rects))
         self.play(
-            LaggedStart(GrowArrow, ys.arrows, lag_ratio=0.8),
+            OldLaggedStart(GrowArrow, ys.arrows, lag_ratio=0.8),
             Write(treat_as_constant)
         )
         self.wait(2)
@@ -277,8 +277,8 @@ class TakePartialDerivatives(Scene):
 
         treat_as_constant.next_to(xs.arrows[1], UP, SMALL_BUFF)
         self.play(
-            LaggedStart(ShowCreation, xs.rects),
-            LaggedStart(GrowArrow, xs.arrows),
+            OldLaggedStart(ShowCreation, xs.rects),
+            OldLaggedStart(GrowArrow, xs.arrows),
             Write(treat_as_constant),
             lag_ratio=0.8
         )
diff --git a/old_projects/highD.py b/old_projects/highD.py
index 113eb5b0..dc8fd529 100644
--- a/old_projects/highD.py
+++ b/old_projects/highD.py
@@ -847,7 +847,7 @@ class DismissProjection(PiCreatureScene):
         for equation, sphere in zip(equations, spheres):
             self.play(
                 Write(equation),
-                LaggedStart(ShowCreation, sphere),
+                OldLaggedStart(ShowCreation, sphere),
             )
         self.wait()
 
@@ -955,7 +955,7 @@ class DismissProjection(PiCreatureScene):
         tup.target.next_to(equation.target, DOWN)
         tup.target.set_color(WHITE)
 
-        self.play(LaggedStart(FadeOut, VGroup(*[
+        self.play(OldLaggedStart(FadeOut, VGroup(*[
             self.equations, self.spheres,
             self.sphere_words, self.sphere_arrow,
             self.descriptor,
@@ -1021,7 +1021,7 @@ class Introduce4DSliders(SliderScene):
         dial_copies = dials.copy()
         dials.set_fill(opacity = 0)
 
-        self.play(LaggedStart(FadeIn, self.sliders))
+        self.play(OldLaggedStart(FadeIn, self.sliders))
         self.play(*[
             Transform(
                 num, dial,
@@ -1603,7 +1603,7 @@ class TwoDBoxExample(Scene):
             UP+RIGHT, SMALL_BUFF
         )
 
-        self.play(LaggedStart(ShowCreation, circles))
+        self.play(OldLaggedStart(ShowCreation, circles))
         self.play(
             ShowCreation(radius),
             Write(r_equals_1)
@@ -1733,7 +1733,7 @@ class ThreeDCubeCorners(Scene):
         group.to_edge(LEFT)
 
         self.play(Write(name, run_time = 2))
-        self.play(LaggedStart(FadeIn, coordinates, run_time = 3))
+        self.play(OldLaggedStart(FadeIn, coordinates, run_time = 3))
         self.wait()
 
 class ShowDistanceFormula(TeacherStudentsScene):
@@ -2166,14 +2166,14 @@ class TwoDBoxWithSliders(TwoDimensionalCase):
         self.wait()
         self.play(ShowCreation(crosses))
         self.play(
-            LaggedStart(MoveToTarget, new_words),
+            OldLaggedStart(MoveToTarget, new_words),
             Animation(crosses)
         )
         self.wait(3)
 
         #Return to original position
         target_vector = np.array(2*[1-np.sqrt(0.5)])
-        self.play(LaggedStart(FadeOut, VGroup(*[
+        self.play(OldLaggedStart(FadeOut, VGroup(*[
             ghost_dials, 
             x_words, y_words, 
             x_arrow, y_arrow, 
@@ -2277,7 +2277,7 @@ class ThreeDBoxExampleWithSliders(SliderScene):
         )
 
         self.play(
-            LaggedStart(FadeIn, sphere_name,),
+            OldLaggedStart(FadeIn, sphere_name,),
             ShowCreation(arrow, rate_func = squish_rate_func(smooth, 0.7, 1)),
             run_time = 3
         )
@@ -2313,7 +2313,7 @@ class ThreeDBoxExampleWithSliders(SliderScene):
             FadeOut(self.sphere_name),
             Transform(self.arrow, new_arrow),
         )
-        self.play(LaggedStart(FadeIn, re_words))
+        self.play(OldLaggedStart(FadeIn, re_words))
         self.wait(2)
 
         self.re_words = re_words
@@ -2387,7 +2387,7 @@ class ThreeDBoxExampleWithSliders(SliderScene):
         self.play(
             Animation(self.sliders),
             FadeOut(self.re_words),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, all_re_ticks,
                 lambda m : (m.shift, shift_vect)
             )
@@ -2459,7 +2459,7 @@ class FourDBoxExampleWithSliders(ThreeDBoxExampleWithSliders):
         coordinate_mobs.next_to(title, DOWN)
 
         self.play(Write(title))
-        self.play(LaggedStart(FadeIn, coordinate_mobs))
+        self.play(OldLaggedStart(FadeIn, coordinate_mobs))
         self.wait()
 
         self.coordinate_mobs = coordinate_mobs
@@ -2547,7 +2547,7 @@ class FourDBoxExampleWithSliders(ThreeDBoxExampleWithSliders):
             re_rects.add(rect)
 
         self.play(FadeIn(re_words))
-        self.play(LaggedStart(DrawBorderThenFill, re_rects, run_time = 3))
+        self.play(OldLaggedStart(DrawBorderThenFill, re_rects, run_time = 3))
         self.wait(2)
 
         self.re_words = re_words
@@ -2578,7 +2578,7 @@ class FourDBoxExampleWithSliders(ThreeDBoxExampleWithSliders):
         )
         self.wait(2)
         re_shift_vect = 0.5*self.sliders[0].unit_size*DOWN
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, self.re_rects,
             lambda m : (m.shift, re_shift_vect),
             path_arc = np.pi
@@ -2610,7 +2610,7 @@ class FourDBoxExampleWithSliders(ThreeDBoxExampleWithSliders):
         brace_text.scale(0.8, about_point = brace_text.get_bottom())
         VGroup(brace, brace_text).set_color(RED)
 
-        self.play(LaggedStart(FadeIn, computation, run_time = 3))
+        self.play(OldLaggedStart(FadeIn, computation, run_time = 3))
         self.play(GrowFromCenter(brace))
         self.play(Write(brace_text, run_time = 2))
         self.wait(16)
@@ -2675,7 +2675,7 @@ class TwoDInnerSphereTouchingBox(TwoDBoxWithSliders, PiCreatureScene):
         self.play(big_inner_circle.move_to, self.circle)
         self.play(big_inner_circle.restore)
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, tangency_points,
             rate_func = double_smooth
         ))
@@ -2772,7 +2772,7 @@ class FiveDBoxExampleWithSliders(FourDBoxExampleWithSliders):
             ShowCreation(re_line),
             Write(re_words, run_time = 2)
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, re_rects,
             rate_func = double_smooth
         ))
@@ -2852,7 +2852,7 @@ class FiveDBoxExampleWithSliders(FourDBoxExampleWithSliders):
 
         self.play(
             Animation(self.sliders),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, re_ticks,
                 lambda m : (m.shift, shift_vect),
                 path_arc = np.pi
@@ -2961,7 +2961,7 @@ class TenDBoxExampleWithSliders(FiveDBoxExampleWithSliders):
         self.wind_down_ambient_movement()
         self.reset_dials(self.n_sliders*[target_x])
         self.play(ShowCreation(re_line))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, re_rects,
             rate_func = double_smooth
         ))
@@ -2987,7 +2987,7 @@ class TenDBoxExampleWithSliders(FiveDBoxExampleWithSliders):
 
         self.play(
             Animation(self.sliders),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, re_ticks,
                 lambda m : (m.shift, shift_vect),
                 path_arc = np.pi
@@ -3131,12 +3131,12 @@ class TenDCornerIsVeryFarAway(TenDBoxExampleWithSliders):
 
         self.set_to_vector(np.zeros(10))
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, re_rects,
                 lambda m : (m.restore,),
                 lag_ratio = 0.3,
             ),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, self.sliders,
                 lambda m : (m.set_value, 1),
                 lag_ratio = 0.3,
@@ -3285,7 +3285,7 @@ class FunHighDSpherePhenomena(Scene):
         items.next_to(h_line, DOWN)
 
         for item in items:
-            self.play(LaggedStart(FadeIn, item, run_time = 2))
+            self.play(OldLaggedStart(FadeIn, item, run_time = 2))
         self.wait()
 
 class TODOBugOnSurface(TODOStub):
@@ -3393,7 +3393,7 @@ class Skeptic(TeacherStudentsScene, SliderScene):
                 for pi in self.students
             ]
         )
-        self.play(Animation(self.sliders), LaggedStart(
+        self.play(Animation(self.sliders), OldLaggedStart(
             ApplyMethod, all_real_estate_ticks,
             lambda m : (m.shift, SMALL_BUFF*LEFT),
             rate_func = wiggle,
@@ -3427,7 +3427,7 @@ class JustBecauseYouCantVisualize(Scene):
         phrase_mob.next_to(ORIGIN, UP)
 
         for part in phrase_mob:
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 FadeIn, part,
                 run_time = 0.05*len(part)
             ))
@@ -3514,7 +3514,7 @@ class Podcast(TeacherStudentsScene):
         q_and_a.next_to(self.teacher.get_corner(UP+LEFT), UP, LARGE_BUFF)
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, self.pi_creatures,
                 lambda pi : (pi.change, "hooray", title)
             ), 
diff --git a/old_projects/leibniz.py b/old_projects/leibniz.py
index 6526267d..26e71d20 100644
--- a/old_projects/leibniz.py
+++ b/old_projects/leibniz.py
@@ -946,7 +946,7 @@ class CountThroughRings(LatticePointScene):
     
         self.add_foreground_mobject(self.lattice_points)
         self.play(FadeIn(circles))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod,
             circles,
             arg_creator = lambda m : (m.set_stroke, PINK, 4),
@@ -2545,7 +2545,7 @@ class IntroduceRecipe(Scene):
                 movers.add(mover)
             index += 1
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             MoveToTarget,
             movers,
             replace_mobject_with_target_in_scene = True
@@ -3112,7 +3112,7 @@ class Show125CircleSimple(LatticePointScene):
                 about_point = self.plane_center
             ),
             ShowCreation(circle),
-            LaggedStart(
+            OldLaggedStart(
                 DrawBorderThenFill,
                 dots,
                 stroke_width = 4,
@@ -3181,7 +3181,7 @@ class SummarizeCountingRule(Show125Circle):
             ShowCreation(circle),
             run_time = 2,
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill,
             dots,
             stroke_width = 4,
@@ -3419,7 +3419,7 @@ class EffectOfPowersOfTwo(LatticePointScene):
         group = groups[0]
 
         self.add(group)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, dots_list[0],
             stroke_width = 4,
             stroke_color = PINK
@@ -3544,7 +3544,7 @@ class IntroduceChi(FactorizationPattern):
             for mob in [chis, arrows, numbers]
         ])
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod,
             numbers,
             lambda m : (m.shift, MED_SMALL_BUFF*UP),
@@ -3637,7 +3637,7 @@ class IntroduceChi(FactorizationPattern):
             self.play(
                 Write(labels),
                 FadeIn(arrows, submobject_mode = "lagged_start"),
-                LaggedStart(
+                OldLaggedStart(
                     DrawBorderThenFill, dots,
                     stroke_width = 4,
                     stroke_color = YELLOW
@@ -4046,7 +4046,7 @@ class ExpandCountWith45(SummarizeCountingRule):
             FadeIn(rect),
             Write(divisor_sum, run_time = 2)
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             MoveToTarget, prime_pairs, 
             run_time = 4,
             lag_ratio = 0.25,
@@ -4054,7 +4054,7 @@ class ExpandCountWith45(SummarizeCountingRule):
         self.remove(prime_pairs)
         product_mobs.set_color(YELLOW)
         self.wait(2)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod,
             product_mobs,
             lambda m : (m.shift, MED_LARGE_BUFF*DOWN),
@@ -4134,14 +4134,14 @@ class CountLatticePointsInBigCircle(LatticePointScene):
         radicals = self.get_radicals()
 
         self.play(
-            LaggedStart(FadeIn, rings),
+            OldLaggedStart(FadeIn, rings),
             Animation(self.lattice_points),
-            LaggedStart(FadeIn, radicals),
+            OldLaggedStart(FadeIn, radicals),
             run_time = 3
         )
         self.add_foreground_mobject(radicals)
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod,
                 dot_groups,
                 lambda m : (m.set_stroke, PINK, 5),
@@ -4197,7 +4197,7 @@ class CountLatticePointsInBigCircle(LatticePointScene):
                 VGroup(self.circle, self.radius).scale_in_place, 2,
                 rate_func=linear,
             ),
-            LaggedStart(
+            OldLaggedStart(
                 DrawBorderThenFill,
                 new_dots,
                 stroke_width = 4,
@@ -4263,7 +4263,7 @@ class AddUpGrid(Scene):
             row_lines[-2].get_left()[0]*RIGHT
         )
 
-        self.play(LaggedStart(ShowCreation, row_lines))
+        self.play(OldLaggedStart(ShowCreation, row_lines))
         self.wait()
 
         self.row_lines = row_lines
@@ -4303,7 +4303,7 @@ class AddUpGrid(Scene):
             chi_sums.add(chi_sum)
             radical.chi_sum = chi_sum
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Write, chi_sums, 
             run_time = 5,
             rate_func = lambda t : t,
@@ -4756,7 +4756,7 @@ class Sponsorship(PiCreatureScene):
 
         self.play(
             morty.change_mode, "raise_right_hand",
-            LaggedStart(DrawBorderThenFill, logo, run_time = 3)
+            OldLaggedStart(DrawBorderThenFill, logo, run_time = 3)
         )
         self.wait()
         self.play(
diff --git a/old_projects/lost_lecture.py b/old_projects/lost_lecture.py
index a8a2cd21..f7f5b0f9 100644
--- a/old_projects/lost_lecture.py
+++ b/old_projects/lost_lecture.py
@@ -189,7 +189,7 @@ class ShowEmergingEllipse(Scene):
         )
         self.wait()
         self.play(
-            LaggedStart(ShowCreation, shuffled_lines),
+            OldLaggedStart(ShowCreation, shuffled_lines),
             Animation(VGroup(e_dot, circle)),
             FadeOut(eccentric_words)
         )
@@ -219,7 +219,7 @@ class ShowEmergingEllipse(Scene):
             Animation(ghost_line)
         )
         self.play(
-            LaggedStart(MoveToTarget, lines, run_time=4),
+            OldLaggedStart(MoveToTarget, lines, run_time=4),
             Animation(VGroup(e_dot, circle))
         )
         self.wait()
@@ -403,7 +403,7 @@ class FeynmanFame(Scene):
 
         # As a physicist
         self.play(self.get_book_intro(books[0]))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Write, feynman_diagram,
             run_time=4
         ))
@@ -411,7 +411,7 @@ class FeynmanFame(Scene):
         self.play(
             self.get_book_intro(books[1]),
             self.get_book_outro(books[0]),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, fd_parts,
                 lambda m: (m.scale, 0),
                 run_time=1
@@ -445,7 +445,7 @@ class FeynmanFame(Scene):
         )
         joke.move_to(objects)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, objects,
             lag_ratio=0.75
         ))
@@ -461,7 +461,7 @@ class FeynmanFame(Scene):
         self.play(
             self.get_book_intro(books[2]),
             self.get_book_outro(books[1]),
-            LaggedStart(FadeOut, joke, run_time=1),
+            OldLaggedStart(FadeOut, joke, run_time=1),
             ApplyMethod(
                 feynman_smile.shift, FRAME_HEIGHT * DOWN,
                 remover=True
@@ -1018,7 +1018,7 @@ class FeynmanElementaryQuote(Scene):
                 self.play(ShowWord(nothing))
                 self.wait(0.2)
                 nothing.sort(lambda p: -p[0])
-                self.play(LaggedStart(
+                self.play(OldLaggedStart(
                     FadeOut, nothing,
                     run_time=1
                 ))
@@ -1128,7 +1128,7 @@ class TableOfContents(Scene):
         scale_factor = 1.2
 
         self.add(title)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, items,
             run_time=1,
             lag_ratio=0.7,
@@ -1225,7 +1225,7 @@ class ShowEllipseDefiningProperty(Scene):
 
         self.add_foreground_mobjects(push_pins, dot)
         self.add(dot_update)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInAndShiftFromDirection, push_pins,
             lambda m: (m, 2 * UP + LEFT),
             run_time=1,
@@ -1484,11 +1484,11 @@ class GeometryProofLand(Scene):
             circle.target = letter
 
         self.play(
-            LaggedStart(MoveToTarget, circles),
+            OldLaggedStart(MoveToTarget, circles),
             run_time=2
         )
         self.add(word_outlines, circles)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, word_outlines,
             run_time=3,
             rate_func=there_and_back,
@@ -1539,7 +1539,7 @@ class ProveEllipse(ShowEmergingEllipse, ShowEllipseDefiningProperty):
 
         self.add(ghost_lines, circle, lines, ep_dot)
         self.play(
-            LaggedStart(MoveToTarget, lines),
+            OldLaggedStart(MoveToTarget, lines),
             Animation(ep_dot),
         )
         self.play(ShowCreation(ellipse))
@@ -1590,7 +1590,7 @@ class ProveEllipse(ShowEmergingEllipse, ShowEllipseDefiningProperty):
             FadeInFromDown(labels[1]),
             GrowArrow(arrows[1]),
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowPassingFlash, ghost_lines_copy
         ))
         self.wait()
@@ -1719,7 +1719,7 @@ class ProveEllipse(ShowEmergingEllipse, ShowEllipseDefiningProperty):
         P_label.next_to(P_dot, UP, SMALL_BUFF)
 
         self.add_foreground_mobjects(self.ellipse)
-        self.play(LaggedStart(Restore, lines))
+        self.play(OldLaggedStart(Restore, lines))
         self.play(
             FadeOut(to_fade),
             ghost_line.set_stroke, YELLOW, 3,
@@ -2050,10 +2050,10 @@ class ProveEllipse(ShowEmergingEllipse, ShowEllipseDefiningProperty):
             line.generate_target()
             line.target.rotate(90 * DEGREES)
         self.play(
-            LaggedStart(FadeIn, ghost_lines),
-            LaggedStart(FadeIn, lines),
+            OldLaggedStart(FadeIn, ghost_lines),
+            OldLaggedStart(FadeIn, lines),
         )
-        self.play(LaggedStart(MoveToTarget, lines))
+        self.play(OldLaggedStart(MoveToTarget, lines))
         self.wait()
 
     def show_orbiting_planet(self):
@@ -2121,7 +2121,7 @@ class EndOfGeometryProofiness(GeometryProofLand):
         underline.match_width(orbital_mechanics)
         underline.next_to(orbital_mechanics, DOWN, SMALL_BUFF)
 
-        self.play(LaggedStart(FadeOutAndShiftDown, geometry_word))
+        self.play(OldLaggedStart(FadeOutAndShiftDown, geometry_word))
         self.play(FadeInFromDown(orbital_mechanics))
         self.play(ShowCreation(underline))
         self.wait()
@@ -2640,12 +2640,12 @@ class AngularMomentumArgument(KeplersSecondLaw):
         self.wait()
         foreground = VGroup(*self.get_mobjects())
         self.play(
-            LaggedStart(GrowArrow, vector_field),
+            OldLaggedStart(GrowArrow, vector_field),
             Animation(foreground)
         )
         for x in range(3):
             self.play(
-                LaggedStart(
+                OldLaggedStart(
                     ApplyFunction, vector_field,
                     lambda mob: (lambda m: m.scale(1.1).set_fill(opacity=1), mob),
                     rate_func=there_and_back,
@@ -2844,7 +2844,7 @@ class IntroduceShapeOfVelocities(AskAboutEllipses, MovingCameraScene):
 
         moving_vector, moving_vector_animation = self.get_velocity_vector_and_update()
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreation, vectors,
             lag_ratio=0.2,
             run_time=3,
@@ -2859,7 +2859,7 @@ class IntroduceShapeOfVelocities(AskAboutEllipses, MovingCameraScene):
         self.wait(10)
         vectors.set_fill(opacity=0.5)
         self.play(
-            LaggedStart(ShowCreation, vectors),
+            OldLaggedStart(ShowCreation, vectors),
             Animation(moving_vector)
         )
         self.wait(5)
@@ -2907,7 +2907,7 @@ class IntroduceShapeOfVelocities(AskAboutEllipses, MovingCameraScene):
                 frame.shift, frame_shift,
                 run_time=2,
             ),
-            LaggedStart(
+            OldLaggedStart(
                 MoveToTarget, vectors,
                 run_time=4,
             ),
@@ -3116,7 +3116,7 @@ class ShowEqualAngleSlices(IntroduceShapeOfVelocities):
             *list(map(ShowCreation, lines))
         )
         self.play(*[
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, fader,
                 lambda m: (m.set_fill, {"opacity": 1}),
                 **kwargs
@@ -3482,8 +3482,8 @@ class ShowEqualAngleSlices(IntroduceShapeOfVelocities):
         self.add(self.orbit)
         self.wait()
         self.play(
-            LaggedStart(ShowCreation, external_angle_lines),
-            LaggedStart(ShowCreation, external_angle_arcs),
+            OldLaggedStart(ShowCreation, external_angle_lines),
+            OldLaggedStart(ShowCreation, external_angle_arcs),
             Animation(difference_vectors),
         )
         self.add_foreground_mobjects(difference_vectors)
@@ -3544,7 +3544,7 @@ class PonderOverOffCenterDiagram(PiCreatureScene):
         words.next_to(rect.get_top(), DOWN)
 
         self.play(
-            LaggedStart(GrowFromCenter, velocity_diagram),
+            OldLaggedStart(GrowFromCenter, velocity_diagram),
             randy.change, "pondering",
             morty.change, "confused",
         )
@@ -3674,7 +3674,7 @@ class UseVelocityDiagramToDeduceCurve(ShowEqualAngleSlices):
         self.play(ApplyWave(ellipse))
         self.play(*list(map(GrowArrow, vectors)))
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 MoveToTarget, vectors,
                 lag_ratio=1,
                 run_time=2
@@ -3859,7 +3859,7 @@ class UseVelocityDiagramToDeduceCurve(ShowEqualAngleSlices):
         )
 
         self.play(
-            LaggedStart(MoveToTarget, vectors),
+            OldLaggedStart(MoveToTarget, vectors),
             highlighted_vector.scale, 0,
             {"about_point": root_dot.get_center()},
             Animation(highlighted_vector),
@@ -3870,7 +3870,7 @@ class UseVelocityDiagramToDeduceCurve(ShowEqualAngleSlices):
         )
         self.remove(vectors, highlighted_vector)
         self.play(
-            LaggedStart(ShowCreation, lines),
+            OldLaggedStart(ShowCreation, lines),
             ShowCreation(highlighted_line),
             Animation(highlighted_vector),
         )
@@ -4014,7 +4014,7 @@ class UseVelocityDiagramToDeduceCurve(ShowEqualAngleSlices):
 
         self.add(ghost_lines)
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 MoveToTarget, lines,
                 lag_ratio=0.1,
                 run_time=8,
@@ -4141,7 +4141,7 @@ class ShowSunVectorField(Scene):
             vector.target.set_stroke(YELLOW, 0.5)
 
         for x in range(3):
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 MoveToTarget, vector_field,
                 rate_func=there_and_back,
                 lag_ratio=0.5,
diff --git a/old_projects/mug.py b/old_projects/mug.py
index 36d20555..6cde3eef 100644
--- a/old_projects/mug.py
+++ b/old_projects/mug.py
@@ -18,7 +18,7 @@ class HappyHolidays(TeacherStudentsScene):
             look_at_arg = FRAME_Y_RADIUS*UP,
             added_anims = [self.teacher.change, "hooray"]
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, hats
         ), Animation(self.pi_creatures))
         self.change_student_modes(
@@ -65,7 +65,7 @@ class HappyHolidays(TeacherStudentsScene):
                 mob, x_start = 2*random.random()*FRAME_X_RADIUS - FRAME_X_RADIUS,
                 **kwargs
             )
-        snowflake_spirils = LaggedStart(
+        snowflake_spirils = OldLaggedStart(
             random_confetti_spiral, snowflakes,
             run_time = 10,
             rate_func = lambda x : x,
@@ -199,7 +199,7 @@ class UtilitiesPuzzleScene(Scene):
             mob.target = Dot(color = mob.get_color())
             mob.target.scale(2)
             mob.target.move_to(mob)
-        self.play(LaggedStart(MoveToTarget, group, run_time = run_time))
+        self.play(OldLaggedStart(MoveToTarget, group, run_time = run_time))
 
 class PauseIt(PiCreatureScene):
     def construct(self):
@@ -232,10 +232,10 @@ class AboutToyPuzzles(UtilitiesPuzzleScene, TeacherStudentsScene, ThreeDScene):
                 run_time = 2,
             ),
             FadeIn(houses[1]),
-            LaggedStart(DrawBorderThenFill, utilities, run_time = 2)
+            OldLaggedStart(DrawBorderThenFill, utilities, run_time = 2)
         )
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ShowCreation, lines, 
                 run_time = 3
             ),
@@ -326,7 +326,7 @@ class AboutToyPuzzles(UtilitiesPuzzleScene, TeacherStudentsScene, ThreeDScene):
             everything.next_to, self.teacher, UP+LEFT,
             self.teacher.restore,
             self.teacher.change, "raise_right_hand", UP+LEFT,
-            LaggedStart(FadeIn, self.students)
+            OldLaggedStart(FadeIn, self.students)
         )
         self.change_student_modes(
             *["pondering"]*3, look_at_arg = everything
@@ -360,14 +360,14 @@ class ThisPuzzleIsHard(UtilitiesPuzzleScene, PiCreatureScene):
         self.add(try_it)
         self.play(Animation(try_it))
         self.play(
-            LaggedStart(DrawBorderThenFill, houses),
-            LaggedStart(GrowFromCenter, utilities),
+            OldLaggedStart(DrawBorderThenFill, houses),
+            OldLaggedStart(GrowFromCenter, utilities),
             try_it.set_width, house.get_width(),
             try_it.fade, 1,
             try_it.move_to, house,
             self.pi_creature.change, "happy",
         )
-        self.play(LaggedStart(FadeIn, puzzle_words))
+        self.play(OldLaggedStart(FadeIn, puzzle_words))
 
         self.add_foreground_mobjects(self.objects)
         self.set_variables_as_attrs(puzzle_words)
@@ -439,7 +439,7 @@ class ThisPuzzleIsHard(UtilitiesPuzzleScene, PiCreatureScene):
         for line_set, mode in zip(line_sets, modes):
             good_lines = VGroup(*line_set[:-2])
             bad_lines = line_set[-2:]
-            self.play(LaggedStart(ShowCreation, good_lines))
+            self.play(OldLaggedStart(ShowCreation, good_lines))
             for bl in bad_lines:
                 self.play(
                     ShowCreation(
@@ -453,7 +453,7 @@ class ThisPuzzleIsHard(UtilitiesPuzzleScene, PiCreatureScene):
                     bl, rate_func = lambda t : smooth(1-t),
                 ))
                 self.remove(bl)
-            self.play(LaggedStart(FadeOut, good_lines))
+            self.play(OldLaggedStart(FadeOut, good_lines))
 
     def ask_meta_puzzle(self):
         randy = self.pi_creature
@@ -484,7 +484,7 @@ class ThisPuzzleIsHard(UtilitiesPuzzleScene, PiCreatureScene):
 
         straight_lines = self.get_straight_lines()
         almost_solution_lines = self.get_almost_solution_lines()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreation, straight_lines,
             run_time = 2,
             lag_ratio = 0.8
@@ -534,10 +534,10 @@ class IntroduceGraph(PiCreatureScene):
             color = WHITE
         )
 
-        self.play(LaggedStart(GrowFromCenter, pi_creatures))
+        self.play(OldLaggedStart(GrowFromCenter, pi_creatures))
         self.play(
-            LaggedStart(ShowCreation, lines),
-            LaggedStart(
+            OldLaggedStart(ShowCreation, lines),
+            OldLaggedStart(
                 ApplyMethod, pi_creatures,
                 lambda pi : (pi.change, "pondering", lines)
             )
@@ -554,7 +554,7 @@ class IntroduceGraph(PiCreatureScene):
             FadeIn(vertices_word),
         )
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, lines,
             lambda l : (l.rotate_in_place, np.pi/12),
             rate_func = wiggle
@@ -612,10 +612,10 @@ class IsK33Planar(UtilitiesPuzzleScene):
 
         self.add(question)
         self.convert_objects_to_dots()
-        self.play(LaggedStart(ShowCreation, straight_lines))
+        self.play(OldLaggedStart(ShowCreation, straight_lines))
         self.play(
             GrowFromCenter(brace),
-            LaggedStart(FadeIn, fancy_name),
+            OldLaggedStart(FadeIn, fancy_name),
         )
         self.play(ReplacementTransform(
             straight_lines, almost_solution_lines,
@@ -684,7 +684,7 @@ class TwoKindsOfViewers(PiCreatureScene, UtilitiesPuzzleScene):
         arrow = Arrow(eulers, objects, color = WHITE)
         self.play(
             GrowArrow(arrow),
-            LaggedStart(DrawBorderThenFill, VGroup(*it.chain(*objects)))
+            OldLaggedStart(DrawBorderThenFill, VGroup(*it.chain(*objects)))
         )
         self.wait()
         self.play(
@@ -713,7 +713,7 @@ class IntroduceRegions(UtilitiesPuzzleScene):
         front_regions = VGroup(*regions[1:])
 
         self.convert_objects_to_dots(run_time = 0)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreation, lines,
             run_time = 3,
         ))
@@ -868,7 +868,7 @@ class AskAboutRegions(IntroduceRegions):
         self.add_foreground_mobjects(lines, objects)
         self.wait()
         self.play(MoveToTarget(front_regions))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, front_regions,
             lambda m : (m.rotate_in_place, np.pi/12),
             rate_func = wiggle,
@@ -923,7 +923,7 @@ class AskAboutRegions(IntroduceRegions):
         def show_lines(line_group):
             lg_copy = line_group.copy()
             lg_copy.set_stroke(WHITE, 6)
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 FadeIn, lg_copy,
                 run_time = 3,
                 rate_func = there_and_back,
@@ -1094,7 +1094,7 @@ class LightUpNodes(IntroduceRegions):
         self.play(*self.get_lit_vertex_animations(lit_vertex))
         self.play(
             FadeIn(dim_word),
-            LaggedStart(GrowArrow, dim_arrows)
+            OldLaggedStart(GrowArrow, dim_arrows)
         )
         self.wait()
         self.play(*list(map(FadeOut, [
@@ -1218,7 +1218,7 @@ class LightUpNodes(IntroduceRegions):
         lines.move_to(vertex)
         random.shuffle(lines.submobjects)
         return [
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, lines,
                 lambda l : (l.set_stroke, YELLOW, 4),
                 rate_func = squish_rate_func(there_and_back, *squish_range),
@@ -1337,7 +1337,7 @@ class ConcludeFiveRegions(LightUpNodes):
         line_sets.target.to_edge(RIGHT)
 
         for lines in line_sets:
-            self.play(LaggedStart(ShowCreation, lines, run_time = 1))
+            self.play(OldLaggedStart(ShowCreation, lines, run_time = 1))
             self.play(MoveToTarget(lines))
         self.wait()
 
@@ -1536,12 +1536,12 @@ class FiveRegionsFourEdgesEachGraph(Scene):
 
         self.play(
             FadeIn(words[0]),
-            LaggedStart(FadeIn, squares, run_time = 1.5)
+            OldLaggedStart(FadeIn, squares, run_time = 1.5)
         )
         self.play(
             FadeIn(words[1]),
-            LaggedStart(ShowCreation, all_edges),
-            LaggedStart(GrowFromCenter, all_vertices),
+            OldLaggedStart(ShowCreation, all_edges),
+            OldLaggedStart(GrowFromCenter, all_vertices),
         )
         self.wait()
 
@@ -1610,7 +1610,7 @@ class FiveRegionsFourEdgesEachGraph(Scene):
                 rate_func = squish_rate_func(smooth, 0.7, 1),
                 run_time = 3,
             ),
-            LaggedStart(
+            OldLaggedStart(
                 MoveToTarget, all_movers,
                 run_time = 3,
                 replace_mobject_with_target_in_scene = True,
@@ -1943,7 +1943,7 @@ class QuestionWrapper(Scene):
         self.play(ShowCreation(screen_rect))
         self.wait()
         for word in question:
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 FadeIn, word,
                 run_time = 0.05*len(word)
             ))
diff --git a/old_projects/mvcr.py b/old_projects/mvcr.py
index be71bb81..f8051f65 100644
--- a/old_projects/mvcr.py
+++ b/old_projects/mvcr.py
@@ -378,12 +378,12 @@ class ComputationalNetwork(MovingCameraScene):
             self.wait()
 
         self.play(
-            LaggedStart(FadeIn, partial_term_rects),
+            OldLaggedStart(FadeIn, partial_term_rects),
             Animation(derivatives)
         )
         self.wait()
         self.play(
-            LaggedStart(FadeOut, partial_term_rects),
+            OldLaggedStart(FadeOut, partial_term_rects),
             Animation(derivatives)
         )
 
@@ -425,7 +425,7 @@ class ComputationalNetwork(MovingCameraScene):
 
         self.play(
             Write(rhs[::3]),
-            LaggedStart(MoveToTarget, derivatives)
+            OldLaggedStart(MoveToTarget, derivatives)
         )
         self.wait()
 
@@ -688,7 +688,7 @@ class ComputationalNetwork(MovingCameraScene):
         result = TexMobject("=", "32", "+", "0")
         result.next_to(rhs, DOWN, aligned_edge=LEFT)
 
-        self.play(LaggedStart(Write, value_labels))
+        self.play(OldLaggedStart(Write, value_labels))
         self.wait()
         self.play(ReplacementTransform(
             full_derivative.copy(), rhs,
diff --git a/old_projects/name_animation.py b/old_projects/name_animation.py
index 49353926..1e6ac676 100644
--- a/old_projects/name_animation.py
+++ b/old_projects/name_animation.py
@@ -45,7 +45,7 @@ class NameAnimationScene(Scene):
         times_n_label.to_edge(UP)
 
         self.play(
-            LaggedStart(FadeIn, name_mob, run_time=3),
+            OldLaggedStart(FadeIn, name_mob, run_time=3),
             ApplyMethod(randy.change, "pondering", pos2, run_time=1),
             FadeIn(times_n_label)
         )
diff --git a/old_projects/nn/part1.py b/old_projects/nn/part1.py
index 8ba506a8..f0b969d2 100644
--- a/old_projects/nn/part1.py
+++ b/old_projects/nn/part1.py
@@ -357,11 +357,11 @@ class ExampleThrees(PiCreatureScene):
 
         self.play(
             FadeIn(three_mob[0]),
-            LaggedStart(FadeIn, three_mob[1])
+            OldLaggedStart(FadeIn, three_mob[1])
         )
         self.wait()
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 DrawBorderThenFill, three_mob_copy,
                 run_time = 3,
                 stroke_color = WHITE,
@@ -577,13 +577,13 @@ class WriteAProgram(Scene):
         choices.next_to(arrow, RIGHT)
 
         self.play(
-            LaggedStart(DrawBorderThenFill, three),
+            OldLaggedStart(DrawBorderThenFill, three),
             ShowCreation(three_rect)
         )
         self.play(Write(numbers))
         self.play(
             ShowCreation(arrow),
-            LaggedStart(FadeIn, choices),
+            OldLaggedStart(FadeIn, choices),
         )
 
         rect = SurroundingRectangle(choices[0], buff = SMALL_BUFF)
@@ -1147,7 +1147,7 @@ class IntroduceEachLayer(PreviewMNistNetwork):
                 )
             )
 
-        self.play(LaggedStart(FadeIn, numbers))
+        self.play(OldLaggedStart(FadeIn, numbers))
         self.play(
             MoveToTarget(example_neuron),
             MoveToTarget(example_num)
@@ -1230,7 +1230,7 @@ class IntroduceEachLayer(PreviewMNistNetwork):
         self.wait()
         for edge_group, layer in zip(network_mob.edge_groups, network_mob.layers[1:]):
             self.play(
-                LaggedStart(FadeIn, layer, run_time = 1),
+                OldLaggedStart(FadeIn, layer, run_time = 1),
                 ShowCreation(edge_group),
             )
         self.wait()
@@ -1271,7 +1271,7 @@ class IntroduceEachLayer(PreviewMNistNetwork):
             )
 
         self.play(ShowCreation(rect))
-        self.play(LaggedStart(FadeIn, labels))
+        self.play(OldLaggedStart(FadeIn, labels))
         self.wait()
         self.play(
             MoveToTarget(neuron),
@@ -1345,7 +1345,7 @@ class DiscussChoiceForHiddenLayers(TeacherStudentsScene):
         for words in two_words, sixteen_words:
             words.next_to(rects, UP)
 
-        neurons_anim = LaggedStart(
+        neurons_anim = OldLaggedStart(
             Indicate, 
             VGroup(*it.chain(*[layer.neurons for layer in layers])),
             rate_func = there_and_back,
@@ -1467,7 +1467,7 @@ class AskAboutLayers(PreviewMNistNetwork):
 
         self.play(
             Write(question, run_time = 1),
-            LaggedStart(
+            OldLaggedStart(
                 GrowFromPoint, arrows,
                 lambda a : (a, a.get_start()),
                 run_time = 2
@@ -1616,7 +1616,7 @@ class BreakUpMacroPatterns(IntroduceEachLayer):
         self.play(ReplacementTransform(
             self.right_line.copy(), right_line
         ))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, VGroup(*equation[3:])
         ))
         self.wait(2)
@@ -1700,7 +1700,7 @@ class BreakUpMacroPatterns(IntroduceEachLayer):
         edge_group = self.network_mob.edge_groups[-1].copy()
         edge_group.set_stroke(YELLOW, 4)
         for x in range(3):
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 ShowCreationThenDestruction, edge_group,
                 run_time = 3
             ))
@@ -1809,7 +1809,7 @@ class BreakUpMicroPatterns(BreakUpMacroPatterns):
         )
         self.play(Blink(randy))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, edges,
             lambda e : (e.restore,),
             run_time = 4
@@ -1857,10 +1857,10 @@ class BreakUpMicroPatterns(BreakUpMacroPatterns):
             randy.change, "hesitant", line
         )
         self.play(Blink(randy))
-        self.play(LaggedStart(FadeIn, digits))
+        self.play(OldLaggedStart(FadeIn, digits))
         self.wait()
         self.play(
-            LaggedStart(FadeIn, Group(*equation[1:])),
+            OldLaggedStart(FadeIn, Group(*equation[1:])),
             randy.change, "pondering", equation
         )
         self.wait(3)
@@ -2162,12 +2162,12 @@ class ManyTasksBreakDownLikeThis(TeacherStudentsScene):
         self.wait()
         self.play(
             GrowFromPoint(arrows[1], arrows[1].get_start()),
-            LaggedStart(FadeIn, syllables, run_time = 1)
+            OldLaggedStart(FadeIn, syllables, run_time = 1)
         )
         self.wait()
         self.play(
             GrowFromPoint(arrows[2], arrows[2].get_start()),
-            LaggedStart(FadeIn, word, run_time = 1)
+            OldLaggedStart(FadeIn, word, run_time = 1)
         )
         self.wait()
 
@@ -2346,8 +2346,8 @@ class IntroduceWeights(IntroduceEachLayer):
             GrowFromPoint(arrow, arrow.get_start()),
             pixels_group.set_height, 3,
             pixels_group.to_edge, RIGHT,
-            LaggedStart(FadeIn, p_labels),
-            LaggedStart(FadeIn, decimals),
+            OldLaggedStart(FadeIn, p_labels),
+            OldLaggedStart(FadeIn, decimals),
         )
         self.wait()
         self.play(
@@ -2405,7 +2405,7 @@ class IntroduceWeights(IntroduceEachLayer):
                 for decimal, r in zip(decimals, random_numbers)
             ]
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, edges,
             lambda m : (m.rotate_in_place, np.pi/24),
             rate_func = wiggle,
@@ -2917,7 +2917,7 @@ class IncludeBias(IntroduceWeights):
         weight_grid = self.weight_grid
         bias_name = self.bias_name
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, weight_grid,
             lambda p : (p.set_fill, 
                 random.choice([GREEN, GREEN, RED]),
@@ -3044,13 +3044,13 @@ class ShowRemainingNetwork(IntroduceWeights):
             )
             last_edges = edges
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ShowCreation, VGroup(*[
                     n.edges_in for n in neurons[7:]
                 ]),
                 run_time = 3,
             ),
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, VGroup(*neurons[7:]),
                 run_time = 3,
             ),
@@ -3075,7 +3075,7 @@ class ShowRemainingNetwork(IntroduceWeights):
 
         self.play(
             FadeIn(words),
-            LaggedStart(
+            OldLaggedStart(
                 GrowArrow, arrows, 
                 run_time = 3,
                 lag_ratio = 0.3,
@@ -3110,7 +3110,7 @@ class ShowRemainingNetwork(IntroduceWeights):
             FadeOut(bb1),
             ReplacementTransform(bb2, bias_count[1]),
             FadeOut(bb3),
-            LaggedStart(FadeOut, bias_arrows)
+            OldLaggedStart(FadeOut, bias_arrows)
         )
         self.wait()
 
@@ -3151,12 +3151,12 @@ class ShowRemainingNetwork(IntroduceWeights):
             MoveToTarget(bias_count),
             Write(added_weights, run_time = 1),
             Write(added_biases, run_time = 1),
-            LaggedStart(
+            OldLaggedStart(
                 ShowCreation, edges,
                 run_time = 4,
                 lag_ratio = 0.3,
             ),
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, neurons,
                 run_time = 4,
                 lag_ratio = 0.3,
@@ -3213,7 +3213,7 @@ class ShowRemainingNetwork(IntroduceWeights):
                 width = 3*random.random()**7
             )
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 MoveToTarget, edges,
                 lag_ratio = 0.6,
                 run_time = 2,
@@ -3529,7 +3529,7 @@ class IntroduceWeightMatrix(NetworkScene):
         pre_brackets.set_fill(opacity = 0)
 
         self.play(FocusOn(self.a_labels[0]))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Indicate, self.a_labels,
             rate_func = there_and_back,
             run_time = 1
@@ -3541,7 +3541,7 @@ class IntroduceWeightMatrix(NetworkScene):
         )
         self.wait()
         self.play(*[
-            LaggedStart(Indicate, mob, rate_func = there_and_back)
+            OldLaggedStart(Indicate, mob, rate_func = there_and_back)
             for mob in (a_labels, a_labels_in_sum)
         ])
         self.wait()
@@ -3613,7 +3613,7 @@ class IntroduceWeightMatrix(NetworkScene):
 
         self.play(ShowCreation(rect))
         for x in range(2):
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 ShowCreationThenDestruction, edges,
                 lag_ratio = 0.8
             ))
@@ -3664,7 +3664,7 @@ class IntroduceWeightMatrix(NetworkScene):
             VGroup(top_row_rect, column_rect).copy(),
             result_terms[0]
         ))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, VGroup(*result_terms[1:])
         ))
         self.wait(2)
@@ -3691,7 +3691,7 @@ class IntroduceWeightMatrix(NetworkScene):
         rowk = self.lower_matrix_rows[-1]
 
         def show_edges(neuron):
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 ShowCreationThenDestruction,
                 neuron.edges_in.copy().set_stroke(GREEN, 5),
                 lag_ratio = 0.7,
@@ -3755,7 +3755,7 @@ class IntroduceWeightMatrix(NetworkScene):
             Transform(self.bias[1].copy(), b_column[0]),
             run_time = 1
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, VGroup(*b_column[1:])
         ))
         self.wait()
@@ -4052,7 +4052,7 @@ class NeuronIsFunction(MoreHonestMNistNetworkPreview):
             FadeOut(self.network_mob),
             *list(map(Animation, [neuron, edges, prev_layer]))
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreationThenDestruction, 
             edges.copy().set_stroke(YELLOW, 4),
         ))
@@ -4278,7 +4278,7 @@ class NextVideo(MoreHonestMNistNetworkPreview, PiCreatureScene):
             video.move_to(pair, LEFT)
             pair.target = video
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             MoveToTarget, neuron_pairs,
             run_time = 3
         ))
diff --git a/old_projects/nn/part2.py b/old_projects/nn/part2.py
index ce0f0c41..4eb561b6 100644
--- a/old_projects/nn/part2.py
+++ b/old_projects/nn/part2.py
@@ -203,7 +203,7 @@ class PreviewLearning(NetworkScene):
         ]
         all_edges = VGroup(*it.chain(*network_mob.edge_groups))
         run_time = kwargs.get("run_time", self.default_activate_run_time)
-        edge_animation = LaggedStart(
+        edge_animation = OldLaggedStart(
             ShowCreationThenDestruction, 
             all_edges.copy().set_fill(YELLOW),
             run_time = run_time,
@@ -312,7 +312,7 @@ class PreviewLearning(NetworkScene):
 
     def get_edge_animation(self):
         edges = VGroup(*it.chain(*self.network_mob.edge_groups))
-        return LaggedStart(
+        return OldLaggedStart(
             ApplyFunction, edges,
             lambda mob : (
                 lambda m : m.rotate_in_place(np.pi/12).set_color(YELLOW),
@@ -363,8 +363,8 @@ class TrainingVsTestData(Scene):
         training_examples.next_to(ORIGIN, LEFT)
         test_examples.next_to(ORIGIN, RIGHT)
         self.play(
-            LaggedStart(FadeIn, training_examples),
-            LaggedStart(FadeIn, test_examples),
+            OldLaggedStart(FadeIn, training_examples),
+            OldLaggedStart(FadeIn, test_examples),
         )
 
         self.training_examples = training_examples
@@ -449,7 +449,7 @@ class MNistDescription(Scene):
         self.add(title, authors)
         self.play(
             Write(link_words, run_time = 2),
-            LaggedStart(GrowArrow, arrows),
+            OldLaggedStart(GrowArrow, arrows),
         )
         self.wait()
 
@@ -472,7 +472,7 @@ class MNistDescription(Scene):
             group.set_height(FRAME_HEIGHT - 1)
             if i == 0:
                 self.play(
-                    LaggedStart(FadeIn, group),
+                    OldLaggedStart(FadeIn, group),
                     FadeOut(word_group),
                 )
             else:
@@ -696,7 +696,7 @@ class IntroduceCostFunction(PreviewLearning):
             run_time = 2,
             submobject_mode = "lagged_start"
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreationThenDestruction, 
             neuron.edges_in.copy().set_stroke(YELLOW, 3),
             run_time = 1.5,
@@ -742,7 +742,7 @@ class IntroduceCostFunction(PreviewLearning):
                 for edge in neuron.edges_in
             ]
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, neuron.edges_in,
             lambda m : (m.rotate_in_place, np.pi/12),
             rate_func = wiggle,
@@ -771,7 +771,7 @@ class IntroduceCostFunction(PreviewLearning):
             self.color_edge_randomly(edge, exp = self.full_edges_exp)
 
         self.play(*[
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, group,
                 run_time = 3,
             )
@@ -807,8 +807,8 @@ class IntroduceCostFunction(PreviewLearning):
         self.play(
             self.network_mob.shift, 0.5*RIGHT,
             ShowCreation(rect),
-            LaggedStart(DrawBorderThenFill, image),
-            LaggedStart(DrawBorderThenFill, neurons),
+            OldLaggedStart(DrawBorderThenFill, image),
+            OldLaggedStart(DrawBorderThenFill, neurons),
             run_time = 1
         )
         self.play(
@@ -879,7 +879,7 @@ class IntroduceCostFunction(PreviewLearning):
             network_mob.edge_groups
         ))))
 
-        self.play(LaggedStart(FadeOut, to_fade, run_time = 1))
+        self.play(OldLaggedStart(FadeOut, to_fade, run_time = 1))
 
     def break_down_cost_function(self):
         layer = self.network_mob.layers[-1]
@@ -1004,8 +1004,8 @@ class IntroduceCostFunction(PreviewLearning):
             cost_group.scale, 0.5,
             cost_group.to_corner, UP+LEFT,
             MoveToTarget(brace),
-            LaggedStart(GrowArrow, arrows),
-            LaggedStart(FadeIn, terms),
+            OldLaggedStart(GrowArrow, arrows),
+            OldLaggedStart(FadeIn, terms),
             FadeIn(sum_term),
             Animation(decimals)
         )
@@ -1018,7 +1018,7 @@ class IntroduceCostFunction(PreviewLearning):
             ]
         ))
         self.wait()
-        self.play(LaggedStart(Indicate, decimals, rate_func = there_and_back))
+        self.play(OldLaggedStart(Indicate, decimals, rate_func = there_and_back))
         self.wait()
         for update in update_decimals:
             update.rate_func = lambda a : smooth(1-a)
@@ -1867,7 +1867,7 @@ class TwoVariableInputSpace(Scene):
         self.play(dot.restore)
         self.play(
             FadeIn(question),
-            LaggedStart(GrowArrow, arrows)
+            OldLaggedStart(GrowArrow, arrows)
         )
         self.wait()
 
@@ -2025,7 +2025,7 @@ class ShowFullCostFunctionGradient(PreviewLearning):
                 run_time = 2,
                 submobject_mode = "lagged_start"
             ),
-            LaggedStart(FadeIn, words),
+            OldLaggedStart(FadeIn, words),
         )
         self.play(*list(map(Write, [lb, rb, lhs])), run_time = 1)
         self.wait()
@@ -2113,7 +2113,7 @@ class HowMinimizingCostMeansBetterTrainingPerformance(IntroduceCostFunction):
             for n1, n2 in zip(values, target_values)
         ]
 
-        self.play(LaggedStart(FadeIn, words, run_time = 1))
+        self.play(OldLaggedStart(FadeIn, words, run_time = 1))
         self.play(*[
             ChangingDecimal(d, update)
             for d, update in zip(decimals, updates)
@@ -2273,8 +2273,8 @@ class NonSpatialGradientIntuition(Scene):
             direction_phrases.add(phrase)
 
         self.play(
-            LaggedStart(MoveToTarget, ws),
-            LaggedStart(FadeIn, direction_phrases)
+            OldLaggedStart(MoveToTarget, ws),
+            OldLaggedStart(FadeIn, direction_phrases)
         )
         self.wait(2)
 
@@ -2312,8 +2312,8 @@ class NonSpatialGradientIntuition(Scene):
             rect.target = words
             rects.add(rect)
 
-        self.play(LaggedStart(ShowCreation, rects))
-        self.play(LaggedStart(MoveToTarget, rects))
+        self.play(OldLaggedStart(ShowCreation, rects))
+        self.play(OldLaggedStart(MoveToTarget, rects))
         self.wait(2)
 
 class SomeConnectionsMatterMoreThanOthers(PreviewLearning):
@@ -2644,7 +2644,7 @@ class GradientNudging(PreviewLearning):
         self.play(
             ReplacementTransform(mover, target),
             FadeIn(words),
-            LaggedStart(GrowArrow, arrows, run_time = 1)
+            OldLaggedStart(GrowArrow, arrows, run_time = 1)
         )
         self.play(FadeOut(target))
         self.play(self.get_edge_change_anim(edges))
@@ -3114,7 +3114,7 @@ class InputRandomData(TestPerformance):
 
         self.play(
             ShowCreation(rect),
-            LaggedStart(
+            OldLaggedStart(
                 DrawBorderThenFill, image, 
                 stroke_width = 0.5
             )
@@ -3148,7 +3148,7 @@ class InputRandomData(TestPerformance):
             for neuron, o in zip(neurons, vect):
                 neuron.generate_target()
                 neuron.target.set_fill(WHITE, opacity = o)
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 MoveToTarget, neurons,
                 run_time = 1
             ))
@@ -3522,13 +3522,13 @@ class RandomlyLabeledImageData(Scene):
             label.target.move_to(labels[i], LEFT)
             label.target.set_color(YELLOW)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, groups,
             run_time = 3,
             lag_ratio = 0.3,
         ))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             MoveToTarget, labels, 
             run_time = 4,
             lag_ratio = 0.5,
@@ -3581,7 +3581,7 @@ class TrainOnImages(PreviewLearning, RandomlyLabeledImageData):
 
             group.to_edge(UP)
             self.add(group)
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 MoveToTarget, edges,
                 lag_ratio = 0.4,
                 run_time = 2,
diff --git a/old_projects/nn/part3.py b/old_projects/nn/part3.py
index fff9bb77..35015173 100644
--- a/old_projects/nn/part3.py
+++ b/old_projects/nn/part3.py
@@ -154,7 +154,7 @@ class InterpretGradientComponents(GradientNudging):
             rects.add(SurroundingRectangle(VGroup(*decimal[-8:])))
         rects.set_color(WHITE)
 
-        self.play(LaggedStart(ShowCreation, rects))
+        self.play(OldLaggedStart(ShowCreation, rects))
         self.play(FadeOut(rects))
 
     def isolate_particular_weights(self):
@@ -335,7 +335,7 @@ class InterpretGradientComponents(GradientNudging):
 
         return [
             self.get_edge_change_anim(edges),
-            LaggedStart(
+            OldLaggedStart(
                 Indicate, w_terms,
                 rate_func = there_and_back,
                 run_time = 1.5,
@@ -407,7 +407,7 @@ class GetLostInNotation(PiCreatureScene):
             mover.target.set_stroke(BLACK, width = 1)
             mover.target.move_to(mover)
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 MoveToTarget, movers,
                 run_time = 2,
             ),
@@ -481,7 +481,7 @@ class ShowAveragingCost(PreviewLearning):
         #Wiggle all edges
         edges = VGroup(*it.chain(*self.network_mob.edge_groups))
         reversed_edges = VGroup(*reversed(edges))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyFunction, edges,
             lambda edge : (
                 lambda m : m.rotate_in_place(np.pi/12).set_color(YELLOW),
@@ -507,7 +507,7 @@ class ShowAveragingCost(PreviewLearning):
             for train_in, train_out in training_data[:n_examples_per_adjustment]:
                 self.show_one_example(train_in, train_out)
                 self.wait(self.time_per_example)
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 ApplyMethod, reversed_edges,
                 lambda m : (m.rotate_in_place, np.pi),
                 run_time = 1,
@@ -585,7 +585,7 @@ class WalkThroughTwoExample(ShowAveragingCost):
 
         edge_groups = self.network_mob.edge_groups
         def adjust_edge_group_anim(edge_group):
-            return LaggedStart(
+            return OldLaggedStart(
                 ApplyFunction, edge_group,
                 lambda edge : (
                     lambda m : m.rotate_in_place(np.pi/12).set_color(YELLOW),
@@ -696,7 +696,7 @@ class WalkThroughTwoExample(ShowAveragingCost):
             )
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 Transform, edges,
                 lambda e : (e, e.target),
                 run_time = 4, 
@@ -733,7 +733,7 @@ class WalkThroughTwoExample(ShowAveragingCost):
 
         self.play(
             output_labels.shift, SMALL_BUFF*RIGHT,
-            LaggedStart(GrowArrow, arrows, run_time = 1)
+            OldLaggedStart(GrowArrow, arrows, run_time = 1)
         )
         self.wait()
 
@@ -769,8 +769,8 @@ class WalkThroughTwoExample(ShowAveragingCost):
         self.remove(two_rect)
         self.play(ReplacementTransform(two_rect.copy(), non_two_rects))
         self.wait()
-        self.play(LaggedStart(FadeOut, non_two_rects, run_time = 1))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(FadeOut, non_two_rects, run_time = 1))
+        self.play(OldLaggedStart(
             ApplyFunction, arrows,
             lambda arrow : (
                 lambda m : m.scale_in_place(0.5).set_color(YELLOW),
@@ -963,7 +963,7 @@ class WalkThroughTwoExample(ShowAveragingCost):
             color = WHITE
         )
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyFunction, edges,
             lambda edge : (
                 lambda m : m.rotate_in_place(np.pi/12).set_stroke(YELLOW),
@@ -976,7 +976,7 @@ class WalkThroughTwoExample(ShowAveragingCost):
             ShowCreation(bright_edges),
             ShowCreation(bright_neurons)
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, bright_neurons,
             lambda m : (m.shift, MED_LARGE_BUFF*LEFT),
             rate_func = there_and_back
@@ -989,9 +989,9 @@ class WalkThroughTwoExample(ShowAveragingCost):
         )
         self.wait()
         for x in range(2):
-            self.play(LaggedStart(ShowCreationThenDestruction, bright_edges))
-        self.play(LaggedStart(ShowCreation, bright_edges))
-        self.play(LaggedStart(
+            self.play(OldLaggedStart(ShowCreationThenDestruction, bright_edges))
+        self.play(OldLaggedStart(ShowCreation, bright_edges))
+        self.play(OldLaggedStart(
             ApplyMethod, dim_neurons,
             lambda m : (m.shift, MED_LARGE_BUFF*LEFT),
             rate_func = there_and_back
@@ -1019,7 +1019,7 @@ class WalkThroughTwoExample(ShowAveragingCost):
         two_activation = two_decimal.number
 
         def get_edge_animation():
-            return LaggedStart(
+            return OldLaggedStart(
                 ShowCreationThenDestruction, bright_edges,
                 lag_ratio = 0.7
             )
@@ -1064,7 +1064,7 @@ class WalkThroughTwoExample(ShowAveragingCost):
         )
         self.play(get_edge_animation())
         self.play(
-            LaggedStart(GrowArrow, neuron_arrows),
+            OldLaggedStart(GrowArrow, neuron_arrows),
             get_edge_animation(),
         )
         self.play(
@@ -1082,12 +1082,12 @@ class WalkThroughTwoExample(ShowAveragingCost):
                 two_decimal,
                 lambda m : m.set_color(WHITE if m.number < 0.8 else BLACK),
             ),
-            LaggedStart(ShowCreation, bright_edges),
+            OldLaggedStart(ShowCreation, bright_edges),
             run_time = 2,
         )
         self.wait()
         self.play(
-            LaggedStart(ShowCreation, neuron_rects),
+            OldLaggedStart(ShowCreation, neuron_rects),
             Write(seeing_words, run_time = 2),
             morty.change, "thinking", seeing_words
         )
@@ -1098,7 +1098,7 @@ class WalkThroughTwoExample(ShowAveragingCost):
             morty.look_at, thinking_words
         )
         self.wait()
-        self.play(LaggedStart(FadeOut, VGroup(
+        self.play(OldLaggedStart(FadeOut, VGroup(
             neuron_rects, two_neuron_rect,
             seeing_words, thinking_words,
             words, morty,
@@ -1161,7 +1161,7 @@ class WalkThroughTwoExample(ShowAveragingCost):
             SMALL_BUFF, aligned_edge = LEFT
         )
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyFunction, prev_neurons,
             lambda neuron : (
                 lambda m : m.scale_in_place(0.5).set_color(YELLOW),
@@ -1186,7 +1186,7 @@ class WalkThroughTwoExample(ShowAveragingCost):
             self.wait(0.5)
             self.play(s_edges.restore)
             self.play(
-                LaggedStart(GrowArrow, arrows),
+                OldLaggedStart(GrowArrow, arrows),
                 neurons.set_stroke, color
             )
             self.play(ApplyMethod(
@@ -1235,12 +1235,12 @@ class WalkThroughTwoExample(ShowAveragingCost):
 
         self.play(ShowCreation(rect))
         self.play(Write(words1))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Indicate, prev_neurons,
             rate_func = wiggle
         ))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreationThenDestruction, edges
         ))
         self.play(Transform(words1, words2))
@@ -1289,7 +1289,7 @@ class WalkThroughTwoExample(ShowAveragingCost):
 
             self.play(
                 FadeIn(VGroup(neuron, decimal, arrow, label)),
-                LaggedStart(ShowCreation, neuron.edges_in),
+                OldLaggedStart(ShowCreation, neuron.edges_in),
             )
             self.play(
                 ReplacementTransform(neuron.edges_in.copy(), new_arrows),
@@ -1309,10 +1309,10 @@ class WalkThroughTwoExample(ShowAveragingCost):
         arrows_to_fade.add(all_dots_plus)
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, VGroup(*it.starmap(VGroup, quads[5:])),
             ),
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, VGroup(*[n.edges_in for n in neurons[5:]])
             ),
             Write(all_dots_plus),
@@ -1357,7 +1357,7 @@ class WalkThroughTwoExample(ShowAveragingCost):
         self.play(
             FadeOut(words_to_fade),
             FadeIn(prev_neurons),
-            LaggedStart(ShowCreation, edges),
+            OldLaggedStart(ShowCreation, edges),
         )
         self.wait()
         for neuron, arrow in zip(neurons, self.prev_neuron_arrows):
@@ -1598,9 +1598,9 @@ class ConstructGradientFromAllTrainingExamples(Scene):
             change.scale_in_place(self.change_scale_val)
 
         self.play(
-            LaggedStart(FadeIn, examples),
-            LaggedStart(ShowCreation, self.h_lines),
-            LaggedStart(ShowCreation, self.v_lines),
+            OldLaggedStart(FadeIn, examples),
+            OldLaggedStart(ShowCreation, self.h_lines),
+            OldLaggedStart(ShowCreation, self.v_lines),
             Write(
                 h_dots, 
                 run_time = 2, 
@@ -1683,17 +1683,17 @@ class ConstructGradientFromAllTrainingExamples(Scene):
         )
         self.play(GrowArrow(arrow_to_averages))
         self.play(
-            LaggedStart(ShowCreation, VGroup(*rects[1:])),
+            OldLaggedStart(ShowCreation, VGroup(*rects[1:])),
             *look_at_anims(rects[1])
         )
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ReplacementTransform, VGroup(*rects[1:]).copy(),
                 lambda m : (m, m.arrow),
                 lag_ratio = 0.7,
             ),
             VGroup(*rects[1:]).set_stroke, WHITE, 1,
-            LaggedStart(
+            OldLaggedStart(
                 ReplacementTransform, VGroup(*self.change_rows[1:]).copy(),
                 lambda m : (m, m.target),
                 lag_ratio = 0.7,
@@ -1745,7 +1745,7 @@ class ConstructGradientFromAllTrainingExamples(Scene):
         ))
         arrow = self.arrow_to_averages
 
-        self.play(LaggedStart(FadeOut, to_fade))
+        self.play(OldLaggedStart(FadeOut, to_fade))
         self.play(
             brackets.shift, shift_vect,
             brackets.set_fill, WHITE, 1,
@@ -1893,7 +1893,7 @@ class OrganizeDataIntoMiniBatches(Scene):
             random.shuffle(mob.submobjects)
         self.arrange_examples_in_grid(examples)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, alt_order_examples,
             lag_ratio = 0.2,
             run_time = 4
@@ -1903,7 +1903,7 @@ class OrganizeDataIntoMiniBatches(Scene):
         self.examples = examples
 
     def shuffle_examples(self):
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, self.examples,
             lambda m : (m.restore,),
             lag_ratio = 0.3,
@@ -1939,7 +1939,7 @@ class OrganizeDataIntoMiniBatches(Scene):
             )
             for row in rows
         ])
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, rects,
             lag_ratio = 0.7,
             rate_func = there_and_back
@@ -1957,7 +1957,7 @@ class OrganizeDataIntoMiniBatches(Scene):
         )
         def indicate_row(row):
             row.sort(lambda p : p[0])
-            return LaggedStart(
+            return OldLaggedStart(
                 ApplyFunction, row,
                 lambda row : (
                     lambda m : m.scale_in_place(0.75).set_color(YELLOW),
@@ -2026,7 +2026,7 @@ class SwimmingInTerms(TeacherStudentsScene):
         terms.arrange(DOWN)
         terms.to_edge(UP)
         self.play(
-            LaggedStart(FadeIn, terms),
+            OldLaggedStart(FadeIn, terms),
             self.get_student_changes(*["horrified"]*3)
         )
         self.wait()
@@ -2221,7 +2221,7 @@ class SimplestNetworkExample(PreviewLearning):
         self.wait()
         self.play(Write(other_terms))
         for x in range(2):
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 Indicate, variables,
                 rate_func = wiggle,
                 run_time = 4,
@@ -2241,7 +2241,7 @@ class SimplestNetworkExample(PreviewLearning):
         ))))
         for mob in to_fade:
             mob.save_state()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, to_fade,
             lambda m : (m.fade, 0.9)
         ))
@@ -2306,7 +2306,7 @@ class SimplestNetworkExample(PreviewLearning):
         not_exponents.set_color(YELLOW)
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ShowCreation, superscript_rects,
                 lag_ratio = 0.8, run_time = 1.5
             ),
@@ -2403,7 +2403,7 @@ class SimplestNetworkExample(PreviewLearning):
             ReplacementTransform(pre_a, a),
             ReplacementTransform(pre_y, y),
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, VGroup(*[m for m in cost_equation if m not in [a, y]])
         ))
         self.play(
@@ -2951,7 +2951,7 @@ class SimplestNetworkExample(PreviewLearning):
     def indicate_everything_on_screen(self):
         everything = VGroup(*self.get_top_level_mobjects())
         everything = VGroup(*[m for m in everything.family_members_with_points() if not m.is_subpath])
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Indicate, everything,
             rate_func = wiggle,
             lag_ratio = 0.2,
@@ -3371,7 +3371,7 @@ class SimplestNetworkExample(PreviewLearning):
         self.play(ShowCreation(rect))
         self.play(FadeIn(comp_graph), FadeOut(rect))
         for x in range(2):
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 Indicate, path_to_C, 
                 rate_func = there_and_back,
                 run_time = 1.5,
@@ -3417,7 +3417,7 @@ class SimplestNetworkExample(PreviewLearning):
         ]
         path_to_C = VGroup(bL, zL, aL, C0)
         def get_path_animation():
-            return LaggedStart(
+            return OldLaggedStart(
                 Indicate, path_to_C, 
                 rate_func = there_and_back,
                 run_time = 1.5,
@@ -3492,7 +3492,7 @@ class SimplestNetworkExample(PreviewLearning):
             for attr in ["aLm1", "zL", "aL", "C0"]
         ])
         def get_path_animation():
-            return LaggedStart(
+            return OldLaggedStart(
                 Indicate, path_to_C, 
                 rate_func = there_and_back,
                 run_time = 1.5,
@@ -3554,7 +3554,7 @@ class SimplestNetworkExample(PreviewLearning):
         prev_layer.next_to(self.last_neurons, LEFT, buff = 0)
         self.remove(prev_layer)
 
-        self.play(LaggedStart(FadeOut, to_fade, run_time = 1))
+        self.play(OldLaggedStart(FadeOut, to_fade, run_time = 1))
         self.play(
             ShowCreation(prev_comp_subgraph, run_time = 1),
             self.chain_rule_equation.to_edge, RIGHT
@@ -3587,7 +3587,7 @@ class SimplestNetworkExample(PreviewLearning):
             ]
         )
         for x in range(2):
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 Indicate, path_to_C, 
                 rate_func = there_and_back,
                 run_time = 1.5,
@@ -3728,7 +3728,7 @@ class GeneralFormulas(SimplestNetworkExample):
             ReplacementTransform(start_labels, all_labels),
             ReplacementTransform(start_arrows, all_arrows),
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreationThenDestruction,
             VGroup(*all_subscript_rects.family_members_with_points()),
             lag_ratio = 0.7
@@ -3764,8 +3764,8 @@ class GeneralFormulas(SimplestNetworkExample):
                     arrows_to_fade.add(neuron.arrow)
 
         self.play(
-            LaggedStart(FadeOut, labels_to_fade),
-            LaggedStart(FadeOut, arrows_to_fade),
+            OldLaggedStart(FadeOut, labels_to_fade),
+            OldLaggedStart(FadeOut, arrows_to_fade),
             run_time = 1
         )
         for neuron, rect in zip(self.chosen_neurons, rects):
@@ -3841,9 +3841,9 @@ class GeneralFormulas(SimplestNetworkExample):
             ReplacementTransform(mob, mob.target)
             for mob in (aj, yj)
         ])
-        self.play(LaggedStart(FadeIn, to_fade_in))
+        self.play(OldLaggedStart(FadeIn, to_fade_in))
         self.wait(2)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Indicate, sum_part,
             rate_func = wiggle,
         ))
@@ -3880,7 +3880,7 @@ class GeneralFormulas(SimplestNetworkExample):
         edges.target.to_edge(UP)
 
         self.play(MoveToTarget(edges))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyFunction, edges,
             lambda e : (
                 lambda m : m.rotate_in_place(np.pi/12).set_color(YELLOW),
@@ -3994,7 +3994,7 @@ class GeneralFormulas(SimplestNetworkExample):
         ))
         self.play(Write(chain_rule))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreationThenDestruction, rects,
             lag_ratio = 0.7,
             run_time = 3
@@ -4092,7 +4092,7 @@ class GeneralFormulas(SimplestNetworkExample):
         for path, path_line in zip(paths, path_lines):
             label = path[-1]
             self.play(
-                LaggedStart(
+                OldLaggedStart(
                     Indicate, path,
                     rate_func = wiggle,
                     run_time = 1,
@@ -4148,7 +4148,7 @@ class GeneralFormulas(SimplestNetworkExample):
             ]
 
         self.play(ShowCreation(deriv_rect))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreationThenDestruction, 
             mid_neuron_outlines
         ))
@@ -4160,11 +4160,11 @@ class GeneralFormulas(SimplestNetworkExample):
         ]), run_time = 4, rate_func = there_and_back)
         self.play(faded_edges.restore)
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 GrowFromCenter, layer.neurons,
                 run_time = 1
             ),
-            LaggedStart(ShowCreation, edges),
+            OldLaggedStart(ShowCreation, edges),
             FadeOut(to_fade)
         )
         for x in range(3):
@@ -4233,7 +4233,7 @@ class LayersOfComplexity(Scene):
         gradient.set_color(RED)
         gradient.next_to(arrow, LEFT)
 
-        self.play(LaggedStart(FadeIn, chain_rule_equations))
+        self.play(OldLaggedStart(FadeIn, chain_rule_equations))
         self.play(GrowFromCenter(brace))
         self.play(GrowArrow(arrow))
         self.play(Write(gradient))
@@ -4330,10 +4330,10 @@ class SponsorFrame(PiCreatureScene):
         t_shirt_words_outline.set_stroke(GREEN, 3)
         self.play(
             morty.change, "hooray", t_shirt_words,
-            LaggedStart(ShowCreation, t_shirt_words_outline),
+            OldLaggedStart(ShowCreation, t_shirt_words_outline),
         )
         self.play(FadeOut(t_shirt_words_outline))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Indicate, url,
             rate_func = wiggle,
             color = PINK,
diff --git a/old_projects/pi_day.py b/old_projects/pi_day.py
index 771ef3c5..0f6ed921 100644
--- a/old_projects/pi_day.py
+++ b/old_projects/pi_day.py
@@ -165,7 +165,7 @@ class AnalysisQuote(Scene):
 
         text.to_edge(LEFT, buff = 1)
 
-        self.play(LaggedStart(FadeIn,text), run_time = 5)
+        self.play(OldLaggedStart(FadeIn,text), run_time = 5)
         self.wait()
         self.play(FadeOut(text))
         self.wait()
@@ -190,7 +190,7 @@ class BernoulliQuote(Scene):
         for char in text.submobjects[151:157]:
             char.set_fill(HIGHLIGHT_COLOR)
 
-        self.play(LaggedStart(FadeIn,text), run_time = 5)
+        self.play(OldLaggedStart(FadeIn,text), run_time = 5)
         self.wait()
         self.play(FadeOut(text))
         self.wait
@@ -399,7 +399,7 @@ class ManyFormulas(Scene):
         formulas.arrange(DOWN, buff = MED_LARGE_BUFF)
         formulas.to_edge(LEFT)
 
-        self.play(LaggedStart(FadeIn, formulas, run_time = 3))
+        self.play(OldLaggedStart(FadeIn, formulas, run_time = 3))
 
         circle = Circle(color = YELLOW, radius = 2)
         circle.to_edge(RIGHT)
@@ -579,10 +579,10 @@ class HeroAndVillain(Scene):
             FadeInFromDown(good_euler),
             Write(good_euler_label)
         )
-        self.play(LaggedStart(FadeIn, tau_words))
+        self.play(OldLaggedStart(FadeIn, tau_words))
         self.wait()
         self.play(FadeInFromDown(bad_euler_pixelated))
-        self.play(LaggedStart(FadeIn, pi_words))
+        self.play(OldLaggedStart(FadeIn, pi_words))
         self.wait(2)
         self.play(
             FadeIn(bad_euler),
@@ -635,7 +635,7 @@ class AnalysisQuote(Scene):
 
         self.add(analysis)
         self.play(*generate_anims2(), rate_func = lambda t : 0.5*smooth(t))
-        self.play(LaggedStart(FadeIn,text), run_time = 5)
+        self.play(OldLaggedStart(FadeIn,text), run_time = 5)
         self.play(FadeIn(pi_formula))
         self.wait()
 
@@ -737,7 +737,7 @@ class ThingsNamedAfterEuler(Scene):
         group.arrange(DOWN, aligned_edge = LEFT)
         group.set_height(FRAME_HEIGHT - 1)
 
-        self.play(LaggedStart(FadeIn, group, lag_ratio = 0.2, run_time = 12))
+        self.play(OldLaggedStart(FadeIn, group, lag_ratio = 0.2, run_time = 12))
         self.wait()
 
 class EulerThinking(Scene):
diff --git a/old_projects/putnam.py b/old_projects/putnam.py
index 8a6d1312..2886ec4b 100644
--- a/old_projects/putnam.py
+++ b/old_projects/putnam.py
@@ -93,7 +93,7 @@ class IntroducePutnam(Scene):
 
         self.add(title)
         self.play(Write(six_hours))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             GrowFromCenter, flat_questions,
             run_time = 3,
         ))
@@ -103,7 +103,7 @@ class IntroducePutnam(Scene):
             *list(map(ShowCreation, rects))
         )
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, out_of_tens,
             run_time = 3,
             stroke_color = YELLOW
@@ -324,10 +324,10 @@ class TwoDCase(Scene):
         question.to_corner(UP+RIGHT)
         self.question = question
 
-        self.play(LaggedStart(DrawBorderThenFill, point_mobs))
+        self.play(OldLaggedStart(DrawBorderThenFill, point_mobs))
         self.play(FadeIn(triangle))
         self.wait()
-        self.play(LaggedStart(Write, point_labels))
+        self.play(OldLaggedStart(Write, point_labels))
         self.wait()
         self.play(Write(question))
         for x in range(self.n_initial_random_choices):
@@ -385,7 +385,7 @@ class TwoDCase(Scene):
             push_pin.fade(1)
             push_pins.add(push_pin)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, push_pins,
             lambda mob : (mob.restore,)
         ))
@@ -535,7 +535,7 @@ class TwoDCase(Scene):
                 rate_func = wiggle,
             )
         )
-        self.play(LaggedStart(FadeIn, proportion, run_time = 1))
+        self.play(OldLaggedStart(FadeIn, proportion, run_time = 1))
         self.wait()
 
         #Non right angles
@@ -923,9 +923,9 @@ class RevisitTwoDCase(TwoDCase):
             words.next_to(rect, UP)
             words.shift_onto_screen()
 
-        self.play(LaggedStart(ShowCreation, center_lines, run_time = 1))
+        self.play(OldLaggedStart(ShowCreation, center_lines, run_time = 1))
         self.play(
-            LaggedStart(FadeIn, arcs, run_time = 1),
+            OldLaggedStart(FadeIn, arcs, run_time = 1),
             Animation(self.point_mobs),
         )
         self.wait()
@@ -995,7 +995,7 @@ class RevisitTwoDCase(TwoDCase):
             ShowCreation(underline)
         )
         self.play(FadeIn(words[0]))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, point_label_groups,
             lambda mob : (mob.restore,),
         ))
@@ -1009,7 +1009,7 @@ class RevisitTwoDCase(TwoDCase):
         self.center_lines_update.update(1)
         self.play(
             FadeIn(words[1]),
-            LaggedStart(GrowFromCenter, center_lines)
+            OldLaggedStart(GrowFromCenter, center_lines)
         )
         for x in range(3):
             self.change_point_mobs_randomly(run_time = 1)
@@ -1242,8 +1242,8 @@ class Rewrite3DRandomProcedure(Scene):
         self.play(FadeIn(words[0]))
         self.play(ShowCreation(cross))
         self.wait()
-        self.play(LaggedStart(FadeIn, words[1]))
-        self.play(LaggedStart(FadeIn, words[2]))
+        self.play(OldLaggedStart(FadeIn, words[1]))
+        self.play(OldLaggedStart(FadeIn, words[2]))
         self.wait(2)
         self.play(Write(words[3]))
         self.wait(3)
@@ -1363,20 +1363,20 @@ class BrilliantPuzzle(PiCreatureScene):
 
         self.remove(students)
         self.play(Write(title))
-        self.play(LaggedStart(GrowFromCenter, students))
+        self.play(OldLaggedStart(GrowFromCenter, students))
         self.play(
-            LaggedStart(Write, tests),
-            LaggedStart(
+            OldLaggedStart(Write, tests),
+            OldLaggedStart(
                 ApplyMethod, students,
                 lambda m : (m.change, "horrified", m.test)
             )
         )
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, students,
             lambda m : (m.change, "conniving")
         ))
-        self.play(LaggedStart(ShowCreation, arrows))
+        self.play(OldLaggedStart(ShowCreation, arrows))
         for x in range(2):
             self.swap_arrows_randomly(arrows)
         self.wait()
diff --git a/old_projects/qa_round_two.py b/old_projects/qa_round_two.py
index 8baeccbc..04ec2a4e 100644
--- a/old_projects/qa_round_two.py
+++ b/old_projects/qa_round_two.py
@@ -36,7 +36,7 @@ class Announcements(PiCreatureScene):
 
         self.play(
             Write(title),
-            LaggedStart(FadeIn, announcements),
+            OldLaggedStart(FadeIn, announcements),
             ShowCreation(underline),
             self.pi_creature.change, "hooray", underline,
         )
@@ -117,7 +117,7 @@ class PowersOfTwo(Scene):
         )
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, curr_po2_outline,
                 rate_func = lambda t : wiggle(t, 8),
                 run_time = 2,
diff --git a/old_projects/quat3d.py b/old_projects/quat3d.py
index af0a8c37..9e9ece25 100644
--- a/old_projects/quat3d.py
+++ b/old_projects/quat3d.py
@@ -216,7 +216,7 @@ class Introduction(QuaternionHistory):
             self.play(
                 FadeInFrom(image, 3 * DOWN),
                 FadeInFromLarge(name),
-                LaggedStart(
+                OldLaggedStart(
                     FadeIn, VGroup(*it.chain(*quote)),
                     lag_ratio=0.3,
                     run_time=2
@@ -271,7 +271,7 @@ class WhoCares(TeacherStudentsScene):
             self.teacher.change, "raise_right_hand"
         )
         # self.play(
-        #     LaggedStart(
+        #     OldLaggedStart(
         #         FadeInFromDown, quotes,
         #         run_time=3
         #     ),
@@ -316,7 +316,7 @@ class WhoCares(TeacherStudentsScene):
         # )
         # self.add_foreground_mobjects(vr_headsets)
         # self.play(
-        #     LaggedStart(
+        #     OldLaggedStart(
         #         FadeInFrom, vr_headsets,
         #         lambda m: (m, UP),
         #     ),
@@ -1209,7 +1209,7 @@ class RuleForQuaternionRotations(EulerAnglesAndGimbal):
         self.wait()
         self.play(
             FadeInFromDown(full_angle_q[0]),
-            LaggedStart(FadeInFromDown, full_angle_q[2:]),
+            OldLaggedStart(FadeInFromDown, full_angle_q[2:]),
         )
         self.play(
             GrowFromCenter(brace),
@@ -1370,7 +1370,7 @@ class ExpandOutFullProduct(TeacherStudentsScene):
             FadeInFromDown(product)
         )
         self.play(
-            LaggedStart(GrowFromCenter, braces),
+            OldLaggedStart(GrowFromCenter, braces),
             self.get_student_changes(
                 "confused", "horrified", "confused"
             )
diff --git a/old_projects/quaternions.py b/old_projects/quaternions.py
index df60e340..2b3c16d1 100644
--- a/old_projects/quaternions.py
+++ b/old_projects/quaternions.py
@@ -454,7 +454,7 @@ class ManyNumberSystems(Scene):
 
         self.add(title)
         self.play(FadeInFromLarge(H_label))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInFromLarge, VGroup(*it.chain(systems[:2], systems[3:])),
             lambda m: (m, 4)
         ))
@@ -476,7 +476,7 @@ class ManyNumberSystems(Scene):
         number_line.add(R_example_dot)
         plane.add(C_example_dot)
         self.wait(2)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod,
             VGroup(
                 H_label,
@@ -598,7 +598,7 @@ class IntroduceHamilton(Scene):
         self.wait()
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, quote,
                 lag_ratio=0.2,
                 run_time=4
@@ -613,7 +613,7 @@ class IntroduceHamilton(Scene):
                 run_time=2,
                 rate_func=squish_rate_func(smooth, 0.5, 1),
             ),
-            LaggedStart(
+            OldLaggedStart(
                 FadeOutAndShiftDown, VGroup(*it.chain(
                     quote, quote_rect, quote_label
                 ))
@@ -788,12 +788,12 @@ class QuaternionHistory(Scene):
                 remover=True
             )
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInFrom, students,
             lambda m: (m, LEFT),
         ))
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, students,
                 lambda pi: (
                     pi.change,
@@ -805,14 +805,14 @@ class QuaternionHistory(Scene):
         )
         blink_wait(3)
         self.play(
-            LaggedStart(FadeInFromDown, images),
-            LaggedStart(FadeInFromLarge, image_labels),
+            OldLaggedStart(FadeInFromDown, images),
+            OldLaggedStart(FadeInFromLarge, image_labels),
             Write(society_title)
         )
         blink_wait(3)
         self.play(
             FadeOutAndShift(hamilton, RIGHT),
-            LaggedStart(
+            OldLaggedStart(
                 FadeOutAndShift, images_with_labels,
                 lambda m: (m, UP)
             ),
@@ -827,13 +827,13 @@ class QuaternionHistory(Scene):
         group = self.get_dissenter_images_quotes_and_names()
         images, quotes, names = group
         self.play(
-            LaggedStart(FadeInFromDown, images),
-            LaggedStart(FadeInFromLarge, names),
+            OldLaggedStart(FadeInFromDown, images),
+            OldLaggedStart(FadeInFromLarge, names),
             lag_ratio=0.75,
             run_time=2,
         )
         for quote in quotes:
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 FadeIn, VGroup(*quote.family_members_with_points()),
                 lag_ratio=0.3
             ))
@@ -907,14 +907,14 @@ class QuaternionHistory(Scene):
             )
 
         def get_change_places():
-            return LaggedStart(
+            return OldLaggedStart(
                 change_single_place, characters,
                 lag_ratio=0.6
             )
 
         self.play(
             Write(title),
-            LaggedStart(FadeInFromDown, characters)
+            OldLaggedStart(FadeInFromDown, characters)
         )
         self.play(
             get_change_places(),
@@ -1106,7 +1106,7 @@ class QuantumSpin(Scene):
         self.add(title, groups)
         self.play()
         self.play(
-            LaggedStart(FadeInFromDown, matrices, run_time=3),
+            OldLaggedStart(FadeInFromDown, matrices, run_time=3),
             *rotations
         )
         for x in range(2):
@@ -1248,12 +1248,12 @@ class IntroduceLinusTheLinelander(Scene):
             linus.look_at, number_line
         )
         self.play(
-            LaggedStart(FadeInFromDown, number_line.numbers),
-            LaggedStart(ShowCreation, number_line.tick_marks),
+            OldLaggedStart(FadeInFromDown, number_line.numbers),
+            OldLaggedStart(ShowCreation, number_line.tick_marks),
             linus.change, "happy"
         )
         self.play(
-            LaggedStart(FadeInFromDown, algebra),
+            OldLaggedStart(FadeInFromDown, algebra),
             linus.look_at, algebra
         )
         self.play(Blink(linus))
@@ -1282,7 +1282,7 @@ class IntroduceLinusTheLinelander(Scene):
         q_marks.next_to(linus.body, UP, buff=0)
         q_marks.set_color_by_gradient(BLUE, GREEN, YELLOW)
         random.shuffle(q_marks.submobjects)
-        q_marks_anim = LaggedStart(
+        q_marks_anim = OldLaggedStart(
             FadeIn, q_marks,
             run_time=15,
             rate_func=there_and_back,
@@ -1476,14 +1476,14 @@ class DefineComplexNumbersPurelyAlgebraically(Scene):
         self.play(Write(number, run_time=1))
         self.play(
             GrowFromCenter(real_brace),
-            LaggedStart(FadeIn, real_label),
+            OldLaggedStart(FadeIn, real_label),
             linus.change, "confused", number,
             run_time=1
         )
         self.wait()
         self.play(
             GrowFromCenter(imag_brace),
-            LaggedStart(FadeIn, imag_label),
+            OldLaggedStart(FadeIn, imag_label),
             run_time=1
         )
         self.play(Blink(linus))
@@ -1657,7 +1657,7 @@ class DefineComplexNumbersPurelyAlgebraically(Scene):
             linus.look_at, final_prouct,
         )
         self.play(
-            LaggedStart(ShowCreation, final_arrows),
+            OldLaggedStart(ShowCreation, final_arrows),
             run_time=3,
         )
         self.play(linus.change, "confused")
@@ -1681,8 +1681,8 @@ class DefineComplexNumbersPurelyAlgebraically(Scene):
         braces = VGroup(real_brace, imag_brace)
         labels = VGroup(real_label, imag_label)
         self.play(
-            LaggedStart(GrowFromCenter, braces),
-            LaggedStart(Write, labels),
+            OldLaggedStart(GrowFromCenter, braces),
+            OldLaggedStart(Write, labels),
         )
         self.wait()
 
@@ -1737,7 +1737,7 @@ class TextbookQuaternionDefinition(TeacherStudentsScene):
         def_rect = SurroundingRectangle(defining_products)
 
         self.play(
-            LaggedStart(FadeInFromDown, defining_products),
+            OldLaggedStart(FadeInFromDown, defining_products),
             self.get_student_changes(*3 * ["confused"]),
             self.teacher.change, "raise_right_hand",
         )
@@ -1800,7 +1800,7 @@ class ProblemsWhereComplexNumbersArise(Scene):
         self.add(problems, v_dots)
         self.play(
             ShowCreation(underline),
-            LaggedStart(FadeInFromDown, title, lag_ratio=0.5),
+            OldLaggedStart(FadeInFromDown, title, lag_ratio=0.5),
             run_time=3
         )
         self.wait()
@@ -1870,7 +1870,7 @@ class WalkThroughComplexMultiplication(ShowComplexMultiplicationExamples):
             z_line, z_label,
             w_line, w_label,
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInFromLarge, VGroup(z_dot, w_dot),
             lambda m: (m, 5),
             lag_ratio=0.8,
@@ -1991,7 +1991,7 @@ class WalkThroughComplexMultiplication(ShowComplexMultiplicationExamples):
         )
         self.wait()
         self.play(FadeOut(VGroup(product_line, product_dot)))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreationThenDestruction, sparkly_plane,
             lag_ratio=0.5,
             run_time=2
@@ -2209,7 +2209,7 @@ class LinusThinksAboutStretching(Scene):
                     lower_line.stretch, scalar, 0,
                     run_time=2
                 ),
-                # LaggedStart(FadeIn, words, run_time=1),
+                # OldLaggedStart(FadeIn, words, run_time=1),
                 FadeInFromLarge(words, 1.0 / scalar),
                 linus.look_at, top_line.number_to_point(scalar)
             )
@@ -2373,10 +2373,10 @@ class IntroduceStereographicProjection(MovingCameraScene):
         v_line.set_height(FRAME_HEIGHT)
         v_line.set_stroke(RED, 5)
 
-        self.play(LaggedStart(FadeInFromLarge, dots))
+        self.play(OldLaggedStart(FadeInFromLarge, dots))
         self.play(FadeInFromLarge(neg_one_dot))
         self.add(lines, neg_one_dot, dots)
-        self.play(LaggedStart(ShowCreation, lines))
+        self.play(OldLaggedStart(ShowCreation, lines))
         self.wait()
         self.play(
             lines.set_stroke, {"width": 0.5},
@@ -2678,8 +2678,8 @@ class IntroduceStereographicProjectionLinusView(IntroduceStereographicProjection
         self.wait()
         for i in [1, 0]:
             self.play(
-                LaggedStart(GrowArrow, arrows[i::2]),
-                LaggedStart(Write, labels[i::2])
+                OldLaggedStart(GrowArrow, arrows[i::2]),
+                OldLaggedStart(Write, labels[i::2])
             )
             self.play(Blink(linus))
 
@@ -3101,7 +3101,7 @@ class IntroduceThreeDNumbers(SpecialThreeDScene):
             line.set_stroke(width=5)
             self.play(
                 ShowCreationThenDestruction(line),
-                LaggedStart(
+                OldLaggedStart(
                     Indicate, group,
                     rate_func=there_and_back,
                     color=line.get_color(),
@@ -3192,8 +3192,8 @@ class IntroduceThreeDNumbers(SpecialThreeDScene):
             )
         self.remove(z_axis_top)
         self.play(
-            LaggedStart(MoveToTarget, group, lag_ratio=0.8),
-            LaggedStart(MoveToTarget, coord_lines, lag_ratio=0.8),
+            OldLaggedStart(MoveToTarget, group, lag_ratio=0.8),
+            OldLaggedStart(MoveToTarget, coord_lines, lag_ratio=0.8),
             FadeOut(self.title),
             FadeIn(new_title),
             run_time=3
@@ -3594,7 +3594,7 @@ class TwoDStereographicProjection(IntroduceFelix):
         north_hemisphere.set_fill(opacity=0.8)
 
         self.play(
-            LaggedStart(ShowCreation, north_lines),
+            OldLaggedStart(ShowCreation, north_lines),
             FadeIn(north_hemisphere)
         )
         self.play(
@@ -3645,7 +3645,7 @@ class TwoDStereographicProjection(IntroduceFelix):
         )
 
         self.play(
-            LaggedStart(ShowCreation, south_lines),
+            OldLaggedStart(ShowCreation, south_lines),
             FadeIn(south_hemisphere)
         )
         self.play(
@@ -3692,8 +3692,8 @@ class TwoDStereographicProjection(IntroduceFelix):
         sphere_arcs.set_stroke(RED)
 
         self.play(
-            LaggedStart(GrowArrow, arrows),
-            LaggedStart(Write, neg_ones)
+            OldLaggedStart(GrowArrow, arrows),
+            OldLaggedStart(Write, neg_ones)
         )
         self.wait(3)
         self.play(
@@ -3961,7 +3961,7 @@ class ShowRotationsJustWithReferenceCircles(TwoDStereographicProjection):
             phi=60 * DEGREES,
         )
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 FadeInFrom, labels,
                 lambda m: (m, UP)
             )
@@ -4204,7 +4204,7 @@ class IntroduceQuaternions(Scene):
         three_axes.arrange(RIGHT, buff=LARGE_BUFF)
         three_axes.next_to(number, DOWN, LARGE_BUFF)
 
-        self.play(LaggedStart(FadeInFromLarge, three_axes))
+        self.play(OldLaggedStart(FadeInFromLarge, three_axes))
         self.wait(2)
 
         self.three_axes = three_axes
@@ -4242,8 +4242,8 @@ class IntroduceQuaternions(Scene):
         VGroup(scalar_word, vector_word).set_color(YELLOW)
 
         self.play(
-            LaggedStart(GrowFromCenter, braces),
-            LaggedStart(
+            OldLaggedStart(GrowFromCenter, braces),
+            OldLaggedStart(
                 FadeInFrom, VGroup(real_word, imag_word),
                 lambda m: (m, UP)
             )
@@ -4431,7 +4431,7 @@ class ShowDotProductCrossProductFromOfQMult(Scene):
         self.add(product)
         self.add(braces)
         self.add(vector_defs)
-        self.play(LaggedStart(FadeInFromLarge, result))
+        self.play(OldLaggedStart(FadeInFromLarge, result))
         self.wait()
 
 
@@ -4627,7 +4627,7 @@ class BreakUpQuaternionMultiplicationInParts(Scene):
             randy.change, "confused", rotate_words,
             ShowCreationThenFadeAround(rotate_words),
         )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInFrom, q_marks,
             lambda m: (m, LEFT),
             lag_ratio=0.8,
@@ -4815,7 +4815,7 @@ class HypersphereStereographicProjection(SpecialThreeDScene):
         words.next_to(brace, DOWN, SMALL_BUFF, LEFT)
 
         self.play(Write(sphere))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInFrom, labels,
             lambda m: (m, IN)
         ))
@@ -5274,7 +5274,7 @@ class RuleOfQuaternionMultiplication(HypersphereStereographicProjection):
             mt.set_value(self.q_tracker.get_value())
 
         self.play(ShowCreation(circle, run_time=2))
-        self.play(LaggedStart(ShowCreation, arrows, lag_ratio=0.25))
+        self.play(OldLaggedStart(ShowCreation, arrows, lag_ratio=0.25))
         self.wait()
         circle.add_updater(lambda c: c.become(get_circle_1i()))
         m_tracker.add_updater(set_to_q_value)
@@ -5909,7 +5909,7 @@ class MentionCommutativity(TeacherStudentsScene):
         self.wait(3)
         self.play(
             FadeInFrom(ji_eq),
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, VGroup(ij_eq, general_eq),
                 lambda m: (m.shift, UP),
                 lag_ratio=0.8,
diff --git a/old_projects/sphere_area.py b/old_projects/sphere_area.py
index 92ecab51..3e3ffb63 100644
--- a/old_projects/sphere_area.py
+++ b/old_projects/sphere_area.py
@@ -147,7 +147,7 @@ class AskAboutShadowRelation(SpecialThreeDScene):
         #         run_time=2
         #     )
         # )
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             UpdateFromAlphaFunc, sphere,
             lambda mob: (mob, lambda m, a: m.set_fill(
                 color=interpolate_color(BLUE_E, YELLOW, a),
@@ -218,7 +218,7 @@ class AskAboutShadowRelation(SpecialThreeDScene):
         self.remove(shadow)
         self.play(*anims)
         self.add_fixed_in_frame_mobjects(shadows, area_labels)
-        self.play(LaggedStart(FadeInFromLarge, area_labels))
+        self.play(OldLaggedStart(FadeInFromLarge, area_labels))
         self.wait()
 
         self.shadows = shadows
@@ -265,7 +265,7 @@ class AskAboutShadowRelation(SpecialThreeDScene):
             mob.target.space_out_submobjects(self.space_out_factor)
         self.play(*map(MoveToTarget, mobjects))
         self.play(*[
-            LaggedStart(
+            OldLaggedStart(
                 ApplyMethod, mob,
                 lambda m: (m.set_fill, YELLOW, 1),
                 rate_func=there_and_back,
@@ -596,9 +596,9 @@ class UnfoldCircles(Scene):
             mob.clear_updaters()
 
         self.play(
-            LaggedStart(Write, circle_copies, lag_ratio=0.7),
-            LaggedStart(Write, R_labels),
-            LaggedStart(ShowCreation, radii_lines),
+            OldLaggedStart(Write, circle_copies, lag_ratio=0.7),
+            OldLaggedStart(Write, R_labels),
+            OldLaggedStart(ShowCreation, radii_lines),
         )
         self.remove(circle_copies)
         self.add(circles, radii_lines, R_labels)
@@ -638,7 +638,7 @@ class UnfoldCircles(Scene):
         self.add(triangles, triangles.copy(), self.area_label)
         self.play(MoveToTarget(triangles[0]))
         self.wait()
-        self.play(LaggedStart(MoveToTarget, triangles))
+        self.play(OldLaggedStart(MoveToTarget, triangles))
         self.wait()
 
     #
@@ -708,7 +708,7 @@ class ShowProjection(SphereCylinderScene):
         pieces.fade(1)
 
         self.add(ghost_sphere)
-        self.play(LaggedStart(Restore, pieces))
+        self.play(OldLaggedStart(Restore, pieces))
         self.wait()
 
         self.pieces = pieces
@@ -727,7 +727,7 @@ class ShowProjection(SphereCylinderScene):
 
         self.play(*map(ShowCreation, proj_lines))
         self.play(
-            LaggedStart(MoveToTarget, pieces),
+            OldLaggedStart(MoveToTarget, pieces),
         )
         self.wait()
 
@@ -1407,7 +1407,7 @@ class TinierAndTinerRectangles(SphereCylinderScene):
             for piece in s1:
                 piece.add(VectorizedPoint(piece.get_center() / 2))
             self.play(
-                LaggedStart(Restore, s2)
+                OldLaggedStart(Restore, s2)
             )
             self.remove(s1)
         self.wait(5)
@@ -1549,7 +1549,7 @@ class JustifyHeightSquish(MovingCameraScene):
         self.wait()
         self.play(
             ShowCreation(hyp),
-            LaggedStart(
+            OldLaggedStart(
                 DrawBorderThenFill, hyp_word,
                 stroke_width=0.5,
                 run_time=1,
@@ -1759,8 +1759,8 @@ class JustifyHeightSquish(MovingCameraScene):
         self.wait()
 
         self.play(
-            LaggedStart(MoveToTarget, movers),
-            LaggedStart(FadeInFromDown, equation[1:4:2])
+            OldLaggedStart(MoveToTarget, movers),
+            OldLaggedStart(FadeInFromDown, equation[1:4:2])
         )
         self.wait()
         self.play(FadeInFrom(equation[-2:], LEFT))
@@ -2141,7 +2141,7 @@ class RotateAllPiecesWithExpansion(ShowProjection):
         self.add(ghost_sphere, sphere)
         self.wait()
         if self.with_expansion:
-            self.play(LaggedStart(
+            self.play(OldLaggedStart(
                 MoveToTarget, sphere
             ))
         self.wait()
@@ -2346,7 +2346,7 @@ class WhatIsSurfaceArea(SpecialThreeDScene):
         self.set_camera_to_default_position()
         self.begin_ambient_camera_rotation()
         # self.add(self.get_axes())
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, pieces,
             lag_ratio=0.2,
         ))
@@ -2654,15 +2654,15 @@ class AskAboutDirectConnection(TeacherStudentsScene, SpecialThreeDScene):
                 *3 * ["pondering"],
                 look_at_arg=group,
             ),
-            LaggedStart(FadeInFromDown, group),
-            LaggedStart(GrowArrow, arrows)
+            OldLaggedStart(FadeInFromDown, group),
+            OldLaggedStart(GrowArrow, arrows)
         )
         self.wait()
         self.play(
             self.teacher.change, "pondering",
             self.students[2].change, "raise_right_hand",
             GrowArrow(direct_arrow),
-            LaggedStart(
+            OldLaggedStart(
                 FadeInFrom, q_marks,
                 lambda m: (m, UP),
                 lag_ratio=0.8,
@@ -2695,7 +2695,7 @@ class ExercisesGiveLearning(MovingCameraScene):
         # Knock down lectures
         self.add(lectures)
         self.play(GrowArrow(arrow1))
-        self.play(LaggedStart(DrawBorderThenFill, bulb))
+        self.play(OldLaggedStart(DrawBorderThenFill, bulb))
         self.play(ShowCreation(cross))
         self.play(
             VGroup(lectures, cross).shift, DOWN,
@@ -2825,7 +2825,7 @@ class SecondProof(SpecialThreeDScene):
 
         self.add(ghost_rings)
         self.play(FadeOut(rings), Animation(shadows))
-        self.play(LaggedStart(Restore, shadows))
+        self.play(OldLaggedStart(Restore, shadows))
         self.wait()
         self.move_camera(phi=40 * DEGREES)
         self.wait(3)
@@ -3158,11 +3158,11 @@ class SecondProof(SpecialThreeDScene):
 
         self.play(
             FadeOut(to_fade),
-            LaggedStart(FadeIn, shadows),
+            OldLaggedStart(FadeIn, shadows),
             self.theta_mob_opacity_tracker.set_value, 0,
         )
         self.play(
-            LaggedStart(Restore, shadows),
+            OldLaggedStart(Restore, shadows),
             ApplyMethod(
                 self.camera.phi_tracker.set_value, 60 * DEGREES,
             ),
diff --git a/old_projects/triples.py b/old_projects/triples.py
index 68959266..c7321f8f 100644
--- a/old_projects/triples.py
+++ b/old_projects/triples.py
@@ -100,11 +100,11 @@ class IntroduceTriples(TeacherStudentsScene):
                 FadeIn(triangle),
                 self.teacher.change_mode, "raise_right_hand"
             )
-            self.play(LaggedStart(FadeIn, a_square))
+            self.play(OldLaggedStart(FadeIn, a_square))
             self.change_student_modes(
                 *["pondering"]*3,
                 look_at_arg = triangle,
-                added_anims = [LaggedStart(FadeIn, b_square)]
+                added_anims = [OldLaggedStart(FadeIn, b_square)]
             )
             self.play(self.teacher.change_mode, "happy")
             for start, target in zip([a_square, b_square], c_square_parts):
@@ -254,7 +254,7 @@ class ShowManyTriples(Scene):
                 )
                 self.wait()
         self.play(FadeOut(triangle))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, 
             VGroup(*[
                 title.target 
@@ -301,7 +301,7 @@ class BabylonianTablets(Scene):
 
         self.add(title)
         self.wait()
-        self.play(LaggedStart(FadeIn, triples, run_time = 5))
+        self.play(OldLaggedStart(FadeIn, triples, run_time = 5))
         self.wait()
 
 class AskAboutFavoriteProof(TeacherStudentsScene):
@@ -403,7 +403,7 @@ class PythagoreanProof(Scene):
             label.target.move_to(square)
             square.add(label)
 
-        self.play(LaggedStart(MoveToTarget, side_labels))
+        self.play(OldLaggedStart(MoveToTarget, side_labels))
 
     def add_new_triangles(self, triangle, added_triangles):
         brace = Brace(added_triangles, DOWN)
@@ -548,7 +548,7 @@ class ReframeOnLattice(PiCreatureScene):
         for new_group in dot_tuple_groups[1:len(initial_examples)]:
             self.play(Transform(dot_tuple_group, new_group))
             self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeIn, all_dots,
             rate_func = there_and_back,
             run_time = 3,
@@ -1506,7 +1506,7 @@ class WriteGeneralFormula(GeneralExample):
             uv_title, triple_title
         ])))
         self.play(*[
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, mob, 
                 run_time = 5,
                 lag_ratio = 0.2
@@ -1685,7 +1685,7 @@ class VisualizeZSquared(Scene):
         dots.sort(lambda p : np.dot(p, UP+RIGHT))
 
         self.add_foreground_mobject(self.coordinate_labels)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, dots,
             stroke_width = 3,
             stroke_color = PINK,
@@ -1701,7 +1701,7 @@ class VisualizeZSquared(Scene):
 
         self.play(
             self.background_planes.set_stroke, None, 1,
-            LaggedStart(
+            OldLaggedStart(
                 FadeIn, color_grid, 
                 run_time = 2
             ),
@@ -1730,7 +1730,7 @@ class VisualizeZSquared(Scene):
         self.play(self.color_grid.set_stroke, None, 3)
         self.wait()
         scale_factor = self.big_dot_radius/self.dot_radius
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, self.dots,
             lambda d : (d.scale_in_place, scale_factor),
             rate_func = there_and_back,
@@ -2053,7 +2053,7 @@ class DrawSingleRadialLine(PointsWeMiss):
         self.play(Indicate(dot))
         self.play(ShowCreation(line), Animation(dot))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, added_dots,
             stroke_color = PINK,
             stroke_width = 4,
@@ -2146,7 +2146,7 @@ class DrawRadialLines(PointsWeMiss):
         )
         self.play(ReplacementTransform(dot, line))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, line.new_dots,
             stroke_width = 4,
             stroke_color = PINK,
@@ -2162,7 +2162,7 @@ class DrawRadialLines(PointsWeMiss):
             dot.target.scale_in_place(1.5)
             dot.target.set_color(RED)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             MoveToTarget, seed_dots,
             run_time = 2
         ))
@@ -2171,7 +2171,7 @@ class DrawRadialLines(PointsWeMiss):
             run_time = 3,
             submobject_mode = "lagged_start"
         ))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             DrawBorderThenFill, new_dots,
             stroke_width = 4,
             stroke_color = PINK,
@@ -2441,7 +2441,7 @@ class ProjectPointsOntoUnitCircle(DrawRadialLines):
             )
             dot.target.set_width(0.01)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             MoveToTarget, dots,
             run_time = 3,
             lag_ratio = 0.2
@@ -2470,7 +2470,7 @@ class ProjectPointsOntoUnitCircle(DrawRadialLines):
             for vect in compass_directions(1000)
         ])
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ShowCreation, lines,
             run_time = 3
         ))
diff --git a/old_projects/turbulence.py b/old_projects/turbulence.py
index 253eee23..230cd3ac 100644
--- a/old_projects/turbulence.py
+++ b/old_projects/turbulence.py
@@ -374,7 +374,7 @@ class EddyReference(Scene):
         label.next_to(new_eddy, UP)
 
         self.play(
-            LaggedStart(ShowCreationThenDestruction, new_eddy),
+            OldLaggedStart(ShowCreationThenDestruction, new_eddy),
             FadeIn(
                 label,
                 rate_func=there_and_back_with_pause,
@@ -462,7 +462,7 @@ class SomeTurbulenceEquations(PiCreatureScene):
         self.wait(3)
         dist_group = VGroup(distribution, brace_group)
         self.play(
-            LaggedStart(FadeOut, VGroup(randy, morty, navier_stokes)),
+            OldLaggedStart(FadeOut, VGroup(randy, morty, navier_stokes)),
             dist_group.scale, 1.5,
             dist_group.center,
             dist_group.to_edge, UP,
@@ -511,7 +511,7 @@ class JokeRingEquation(Scene):
                 ShowCreation(arrows[i])
             )
             self.wait()
-        self.play(LaggedStart(FadeIn, items[2:]))
+        self.play(OldLaggedStart(FadeIn, items[2:]))
         self.wait()
         self.play(FadeOut(arrows))
         self.wait()
@@ -588,7 +588,7 @@ class CarefulWithLasers(TeacherStudentsScene):
             )
         laser.add_updater(update_laser)
 
-        self.play(LaggedStart(FadeInFromDown, self.pi_creatures, run_time=1))
+        self.play(OldLaggedStart(FadeInFromDown, self.pi_creatures, run_time=1))
         self.add(self.pi_creatures, laser)
         for pi in self.pi_creatures:
             pi.add_updater(lambda p: p.look_at(laser[1]))
@@ -711,7 +711,7 @@ class AskAboutTurbulence(TeacherStudentsScene):
         )
         self.play(
             ShowCreation(h_line),
-            LaggedStart(
+            OldLaggedStart(
                 FadeOutAndShiftDown, self.pi_creatures,
                 run_time=1,
                 lag_ratio=0.8
@@ -736,7 +736,7 @@ class AskAboutTurbulence(TeacherStudentsScene):
         words[1].shift(FRAME_WIDTH * RIGHT / 4)
         self.play(
             ShowCreation(v_line),
-            LaggedStart(FadeInFromDown, words)
+            OldLaggedStart(FadeInFromDown, words)
         )
         self.wait()
 
@@ -1006,7 +1006,7 @@ class ShowNavierStokesEquations(Scene):
 
         self.play(FadeInFromDown(equations))
         self.play(Write(name))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInFrom, variables,
             lambda m: (m, RIGHT),
         ))
@@ -1019,9 +1019,9 @@ class ShowNavierStokesEquations(Scene):
         )
         self.play(ShowCreationThenFadeAround(parts[0]))
         self.wait()
-        self.play(LaggedStart(FadeInFrom, labels[1:]))
+        self.play(OldLaggedStart(FadeInFrom, labels[1:]))
         self.wait(3)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeOut, VGroup(*it.chain(labels, variables, newtons_second))
         ))
 
@@ -1089,7 +1089,7 @@ class ShowNavierStokesEquations(Scene):
         self.wait(2)
         to_fade = VGroup(question, q_arrow, axes, graph)
         self.play(
-            LaggedStart(FadeOut, to_fade),
+            OldLaggedStart(FadeOut, to_fade),
             morty.change, "pondering"
         )
         self.wait(2)
@@ -1196,7 +1196,7 @@ class NewtonsSecond(Scene):
         self.wait()
         square.restore()
         self.play(
-            LaggedStart(GrowArrow, arrows)
+            OldLaggedStart(GrowArrow, arrows)
         )
         square.add(arrows)
         self.play(
@@ -1243,7 +1243,7 @@ class FiguresOfFluidDynamics(Scene):
         image_groups.arrange_in_grid(2, 3)
         image_groups.set_height(FRAME_HEIGHT - 1)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeInFromDown, image_groups,
             lag_ratio=0.5,
             run_time=3
@@ -1582,7 +1582,7 @@ class VortedStretching(ThreeDScene):
         flow_lines = self.get_flow_lines(circles)
 
         self.add(circles, flow_lines)
-        self.play(LaggedStart(ShowCreation, circles))
+        self.play(OldLaggedStart(ShowCreation, circles))
         self.wait(5)
         self.play(Transform(circles, tall_circles, run_time=3))
         self.wait(10)
diff --git a/old_projects/uncertainty.py b/old_projects/uncertainty.py
index 62e273cc..54e1ec5a 100644
--- a/old_projects/uncertainty.py
+++ b/old_projects/uncertainty.py
@@ -758,7 +758,7 @@ class TwoCarsAtRedLight(Scene):
         self.play(
             self.get_flashes(car1, num_flashes = 2),
             self.get_flashes(car2, num_flashes = 2),
-            LaggedStart(FadeIn, VGroup(
+            OldLaggedStart(FadeIn, VGroup(
                 axes, time_label, y_title,
             ))
         )
@@ -868,7 +868,7 @@ class TwoCarsAtRedLight(Scene):
             freq_graph.points[0] = frequency_axes.coords_to_point(0, 0)
             freq_graph.points[-1] = frequency_axes.coords_to_point(2, 0)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeOut, VGroup(
                 self.time_graph_label,
                 self.frequency_graph_label,
@@ -1183,7 +1183,7 @@ class FourierRecapScene(DrawFrequencyPlot):
         )
         self.wait()
         self.play(
-            LaggedStart(FadeIn, self.frequency_axes),
+            OldLaggedStart(FadeIn, self.frequency_axes),
             ReplacementTransform(
                 time_graph.copy(),
                 fourier_graph,
@@ -1197,7 +1197,7 @@ class FourierRecapScene(DrawFrequencyPlot):
             ),
         )
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Indicate, self.frequency_axes.x_axis.numbers,
             run_time = 4,
             rate_func = wiggle,
@@ -1792,7 +1792,7 @@ class IntroduceDopplerRadar(Scene):
 
         self.remove(graph_draw, pulse, randy_look_at, axes_anim)
         self.add(axes)
-        self.play(LaggedStart(FadeOut, VGroup(
+        self.play(OldLaggedStart(FadeOut, VGroup(
             sum_graph, randy,
             pulse_graph.arrow, pulse_graph.label,
             echo_graph.arrow, echo_graph.label,
@@ -2062,7 +2062,7 @@ class DopplerFormulaInsert(Scene):
 
         self.add(randy)
         self.play(
-            LaggedStart(FadeIn, formula),
+            OldLaggedStart(FadeIn, formula),
             randy.change, "pondering", randy.get_bottom(),
         )
         self.play(Blink(randy))
@@ -2227,11 +2227,11 @@ class TimeAndFrequencyGivePositionAndVelocity(IntroduceDopplerRadar):
         self.play(ShowCreation(graph))
         self.play(
             GrowArrow(arrow),
-            LaggedStart(FadeIn, time, run_time = 1)
+            OldLaggedStart(FadeIn, time, run_time = 1)
         )
         self.play(
             GrowFromCenter(brace),
-            LaggedStart(FadeIn, frequency, run_time = 1)
+            OldLaggedStart(FadeIn, frequency, run_time = 1)
         )
         self.wait()
         self.play(
@@ -2419,7 +2419,7 @@ class AmbiguityInLongEchos(IntroduceDopplerRadar, PiCreatureScene):
             look_at_arg = brace,
         ))
         self.play(Blink(randy))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             FadeOut, VGroup(
                 randy.bubble, randy.bubble.content, 
                 brace, words,
@@ -2461,7 +2461,7 @@ class AmbiguityInLongEchos(IntroduceDopplerRadar, PiCreatureScene):
         pulses = self.get_pulses()
 
         self.play(
-            LaggedStart(GrowFromCenter, objects[1:]),
+            OldLaggedStart(GrowFromCenter, objects[1:]),
             FadeOut(curr_graph),
             randy.change, "pondering"
         )
@@ -2552,8 +2552,8 @@ class AmbiguityInLongEchos(IntroduceDopplerRadar, PiCreatureScene):
                 {"buff" : SMALL_BUFF},
                 rate_func = squish_rate_func(smooth, 0.5, 1)
             ),
-            LaggedStart(FadeOut, self.objects),
-            LaggedStart(FadeOut, VGroup(
+            OldLaggedStart(FadeOut, self.objects),
+            OldLaggedStart(FadeOut, VGroup(
                 self.curr_graph, self.dish, self.pi_creature
             )),
             run_time = 2
@@ -2626,7 +2626,7 @@ class AmbiguityInLongEchos(IntroduceDopplerRadar, PiCreatureScene):
         self.play(
             FadeOut(self.axes),
             FadeOut(self.first_echo_graph),
-            LaggedStart(FadeIn, objects),
+            OldLaggedStart(FadeIn, objects),
             FadeIn(self.dish)
         )
         self.add(*continual_anims)
@@ -3134,10 +3134,10 @@ class ShowMomentumFormula(IntroduceDeBroglie, TeacherStudentsScene):
             xi_words.next_to, added_xi_words, UP,
         )
         self.play(
-            LaggedStart(ShowCreation, v_lines),
+            OldLaggedStart(ShowCreation, v_lines),
             self.get_student_changes(*["pondering"]*3)
         )
-        self.play(LaggedStart(FadeOut, v_lines))
+        self.play(OldLaggedStart(FadeOut, v_lines))
         self.wait()
 
         self.formula_labels = VGroup(
@@ -3464,7 +3464,7 @@ class HangingWeightsScene(MovingCameraScene):
 
         self.play(
             ShowCreation(ceiling),
-            LaggedStart(ShowCreation, springs)
+            OldLaggedStart(ShowCreation, springs)
         )
 
     def setup_weights(self):
@@ -3487,7 +3487,7 @@ class HangingWeightsScene(MovingCameraScene):
         weights.set_color_by_gradient(BLUE_D, BLUE_E, BLUE_D)
         weights.set_stroke(WHITE, 1)
 
-        self.play(LaggedStart(GrowFromCenter, weights))
+        self.play(OldLaggedStart(GrowFromCenter, weights))
         self.add(self.t_tracker_walk)
         self.add(self.spring_update_anim)
         self.add(*weight_anims)
@@ -4454,7 +4454,7 @@ class Promotion(PiCreatureScene):
         )
         self.wait(2)
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ApplyFunction, aops_logo,
                 lambda mob : (lambda m : m.shift(0.2*UP).set_color(YELLOW), mob),
                 rate_func = there_and_back, 
@@ -4543,7 +4543,7 @@ class PuzzleStatement(Scene):
         """, alignment = "")
         words.set_width(FRAME_WIDTH - 2)
         words.next_to(group, DOWN, LARGE_BUFF)
-        self.play(LaggedStart(FadeIn, words, run_time = 5, lag_ratio = 0.2))
+        self.play(OldLaggedStart(FadeIn, words, run_time = 5, lag_ratio = 0.2))
         self.wait(2)
 
 class UncertaintyEndScreen(PatreonEndScreen):
diff --git a/old_projects/wallis.py b/old_projects/wallis.py
index c3b646b1..c3b6b3ec 100644
--- a/old_projects/wallis.py
+++ b/old_projects/wallis.py
@@ -431,11 +431,11 @@ class SridharWatchingScene(PiCreatureScene):
         basel.set_color(YELLOW)
         wallis.set_color(BLUE)
 
-        self.play(LaggedStart(DrawBorderThenFill, laptop))
+        self.play(OldLaggedStart(DrawBorderThenFill, laptop))
         self.play(sridhar.change, "pondering", laptop.screen)
         self.wait()
         self.play(ShowCreation(bubble))
-        self.play(LaggedStart(FadeIn, basel))
+        self.play(OldLaggedStart(FadeIn, basel))
         self.play(
             ReplacementTransform(basel.copy(), wallis),
             GrowFromPoint(arrow, arrow.get_top())
@@ -443,7 +443,7 @@ class SridharWatchingScene(PiCreatureScene):
         self.wait(4)
         self.play(sridhar.change, "thinking", wallis)
         self.wait(4)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyFunction,
             VGroup(*list(laptop) + [bubble, basel, arrow, wallis, sridhar]),
             lambda mob: (lambda m: m.set_color(BLACK).fade(1).scale(0.8), mob),
@@ -534,8 +534,8 @@ class ShowProduct(Scene):
             self.wait(0.5)
         N = len(parts)
         self.play(
-            LaggedStart(ShowCreation, lines[N - 1:], lag_ratio=0.2),
-            LaggedStart(FadeIn, dots[N:], lag_ratio=0.2),
+            OldLaggedStart(ShowCreation, lines[N - 1:], lag_ratio=0.2),
+            OldLaggedStart(FadeIn, dots[N:], lag_ratio=0.2),
             brace.stretch, 1.2, 0, {"about_edge": LEFT},
             ChangeDecimalToValue(
                 decimal, partial_products[-1],
@@ -618,7 +618,7 @@ class ShowProduct(Scene):
 
         self.play(
             ShowCreation(lines),
-            LaggedStart(FadeIn, dots, lag_ratio=0.1),
+            OldLaggedStart(FadeIn, dots, lag_ratio=0.1),
             run_time=3,
             rate_func=linear,
         )
@@ -1018,8 +1018,8 @@ class DistanceProductScene(MovingCameraScene):
         if not hasattr(self, "numeric_distance_labels"):
             self.get_numeric_distance_labels()
         if show_line_creation:
-            anims.append(LaggedStart(ShowCreation, self.distance_lines))
-        anims.append(LaggedStart(FadeIn, self.numeric_distance_labels))
+            anims.append(OldLaggedStart(ShowCreation, self.distance_lines))
+        anims.append(OldLaggedStart(FadeIn, self.numeric_distance_labels))
 
         self.play(*anims)
 
@@ -1083,8 +1083,8 @@ class IntroduceDistanceProduct(DistanceProductScene):
 
         self.play(ShowCreation(circle))
         self.play(
-            LaggedStart(ShowCreation, lh_dots),
-            LaggedStart(GrowArrow, lh_dot_arrows),
+            OldLaggedStart(ShowCreation, lh_dots),
+            OldLaggedStart(GrowArrow, lh_dot_arrows),
             Write(evenly_space_dots_label)
         )
         self.wait()
@@ -1108,9 +1108,9 @@ class IntroduceDistanceProduct(DistanceProductScene):
         observer.to_edge(RIGHT)
 
         self.play(
-            LaggedStart(FadeOut, self.lh_dots),
-            LaggedStart(FadeIn, lighthouses),
-            LaggedStart(SwitchOn, lights),
+            OldLaggedStart(FadeOut, self.lh_dots),
+            OldLaggedStart(FadeIn, lighthouses),
+            OldLaggedStart(SwitchOn, lights),
         )
         self.wait()
         self.play(FadeIn(observer))
@@ -1160,8 +1160,8 @@ class IntroduceDistanceProduct(DistanceProductScene):
         light_rings = VGroup(*it.chain(*self.lights))
 
         self.play(
-            LaggedStart(ShowCreation, lines),
-            LaggedStart(Write, labels),
+            OldLaggedStart(ShowCreation, lines),
+            OldLaggedStart(Write, labels),
         )
         circle_group = VGroup(*self.get_top_level_mobjects())
         self.wait()
@@ -1181,7 +1181,7 @@ class IntroduceDistanceProduct(DistanceProductScene):
             circle_group.scale, 0.8, {"about_point": FRAME_Y_RADIUS * DOWN}
         )
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, light_rings,
             lambda m: (m.set_fill, {"opacity": 2 * m.get_fill_opacity()}),
             rate_func=there_and_back,
@@ -1255,9 +1255,9 @@ class IntroduceDistanceProduct(DistanceProductScene):
             Write(distance_product_label)
         )
         line_copies = lines.copy().set_color(RED)
-        self.play(LaggedStart(ShowCreationThenDestruction, line_copies))
+        self.play(OldLaggedStart(ShowCreationThenDestruction, line_copies))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyFunction, light_rings,
             lambda mob: (
                 lambda m: m.shift(
@@ -1329,7 +1329,7 @@ class Lemma1(DistanceProductScene):
     def add_circle_group(self):
         self.circle.to_corner(DL)
         circle_group = self.get_circle_group()
-        self.play(LaggedStart(FadeIn, VGroup(
+        self.play(OldLaggedStart(FadeIn, VGroup(
             *circle_group.family_members_with_points())))
 
     def state_lemma_premise(self):
@@ -1661,12 +1661,12 @@ class FromGeometryToAlgebra(DistanceProductScene):
         arrows.set_color(YELLOW)
         self.play(
             ReplacementTransform(unit_circle_words, roots_of_unity_words),
-            LaggedStart(GrowArrow, arrows)
+            OldLaggedStart(GrowArrow, arrows)
         )
         self.wait()
         self.play(
             complex_plane_words.move_to, word_group,
-            LaggedStart(FadeOut, VGroup(*it.chain(
+            OldLaggedStart(FadeOut, VGroup(*it.chain(
                 arrows, roots_of_unity_words
             )))
         )
@@ -1905,11 +1905,11 @@ class FromGeometryToAlgebra(DistanceProductScene):
             n_term.shift(0.25 * SMALL_BUFF * DR)
             n_terms.add(n_term)
 
-        self.play(LaggedStart(FadeOut, VGroup(*it.chain(
+        self.play(OldLaggedStart(FadeOut, VGroup(*it.chain(
             L1_rhs, self.outer_arrows, self.L_labels, self.outer_arrow,
             self.angle_line, self.ghost_angle_line
         ))))
-        self.play(LaggedStart(SwitchOn, new_lights), morty.look_at, new_lights)
+        self.play(OldLaggedStart(SwitchOn, new_lights), morty.look_at, new_lights)
         self.play(Transform(sevens, n_terms))
         self.wait()
         self.play(Blink(morty))
@@ -2087,7 +2087,7 @@ class PlugObserverIntoPolynomial(DistanceProductScene):
         # Show distances
         self.play(ShowCreation(rhs_rect))
         self.play(
-            LaggedStart(ShowCreation, lines),
+            OldLaggedStart(ShowCreation, lines),
             Animation(dot)
         )
 
@@ -2248,7 +2248,7 @@ class PlugObserverIntoPolynomial(DistanceProductScene):
 
         # Talk through current example
         light_rings = VGroup(*it.chain(self.lights))
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, light_rings,
             lambda m: (m.shift, MED_SMALL_BUFF * UP),
             rate_func=wiggle
@@ -2660,8 +2660,8 @@ class DistanceProductIsChordF(PlugObserverIntoPolynomial):
         self.play(Write(fraction_words))
         self.wait()
         self.play(
-            LaggedStart(ShowCreation, lines),
-            LaggedStart(FadeIn, labels),
+            OldLaggedStart(ShowCreation, lines),
+            OldLaggedStart(FadeIn, labels),
         )
         self.play(
             FadeIn(black_rect),
@@ -2771,8 +2771,8 @@ class ProveLemma2(PlugObserverIntoPolynomial):
             *list(map(SurroundingRectangle, [dot, stacked_labels[0]])))
 
         self.play(
-            LaggedStart(ShowCreation, lines),
-            LaggedStart(FadeIn, labels),
+            OldLaggedStart(ShowCreation, lines),
+            OldLaggedStart(FadeIn, labels),
         )
         self.play(
             FadeIn(black_rect),
@@ -2840,7 +2840,7 @@ class ProveLemma2(PlugObserverIntoPolynomial):
 
         self.play(ShowCreation(lhs_rect))
         self.add_foreground_mobject(roots_of_unity_circle)
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             ApplyMethod, roots_of_unity_circle,
             lambda m: (m.restore,)
         ))
@@ -3021,8 +3021,8 @@ class ArmedWithTwoKeyFacts(TeacherStudentsScene, DistanceProductScene):
             group = VGroup(lines, observer, label)
             self.play(
                 FadeIn(circle),
-                LaggedStart(FadeIn, VGroup(*it.chain(lights))),
-                LaggedStart(
+                OldLaggedStart(FadeIn, VGroup(*it.chain(lights))),
+                OldLaggedStart(
                     FadeIn, VGroup(
                         *it.chain(group.family_members_with_points()))
                 ),
@@ -3031,7 +3031,7 @@ class ArmedWithTwoKeyFacts(TeacherStudentsScene, DistanceProductScene):
             )
         wallis_product.move_to(labels).to_edge(RIGHT)
         self.play(
-            LaggedStart(FadeIn, wallis_product),
+            OldLaggedStart(FadeIn, wallis_product),
             self.teacher.change_mode, "hooray",
             self.get_student_changes(
                 *["thinking"] * 3, look_at_arg=wallis_product)
@@ -3128,9 +3128,9 @@ class KeeperAndSailor(DistanceProductScene, PiCreatureScene):
             self.add_foreground_mobject(lights)
         self.add_foreground_mobject(words)
         self.play(
-            LaggedStart(FadeIn, VGroup(*it.chain(lights))),
-            LaggedStart(FadeIn, lighthouses),
-            LaggedStart(GrowArrow, arrows),
+            OldLaggedStart(FadeIn, VGroup(*it.chain(lights))),
+            OldLaggedStart(FadeIn, lighthouses),
+            OldLaggedStart(GrowArrow, arrows),
         )
         self.remove_foreground_mobjects(words)
         self.play(FadeOut(words), FadeOut(arrows))
@@ -3149,7 +3149,7 @@ class KeeperAndSailor(DistanceProductScene, PiCreatureScene):
             pi.dot.next_to(pi, LEFT)
             pi.dot.set_fill(opacity=0)
 
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Succession, observers,
             lambda m: (FadeIn, m, ApplyMethod, m.change, "wave_1")
         ))
@@ -3253,7 +3253,7 @@ class KeeperAndSailor(DistanceProductScene, PiCreatureScene):
             ShowCreation(fraction[1])
         )
         self.wait()
-        self.play(LaggedStart(FadeIn, sailor_line_lengths))
+        self.play(OldLaggedStart(FadeIn, sailor_line_lengths))
         self.play(ReplacementTransform(
             sailor_line_lengths.copy(), sailor_dp_column[0]
         ))
@@ -3376,10 +3376,10 @@ class KeeperAndSailor(DistanceProductScene, PiCreatureScene):
         # Animations
         self.replace_lighthouses_with_labels()
         self.play(
-            LaggedStart(FadeIn, product_parts),
-            LaggedStart(FadeIn, sailor_lines,
+            OldLaggedStart(FadeIn, product_parts),
+            OldLaggedStart(FadeIn, sailor_lines,
                         rate_func=there_and_back, remover=True),
-            LaggedStart(FadeIn, keeper_lines,
+            OldLaggedStart(FadeIn, keeper_lines,
                         rate_func=there_and_back, remover=True),
         )
         sailor_lines.restore()
@@ -3662,7 +3662,7 @@ class KeeperAndSailor(DistanceProductScene, PiCreatureScene):
             cw_product_parts.restore,
         )
         term_rect = cw_term_rects[0].copy()
-        self.play(LaggedStart(ShowCreationThenDestruction, cw_label_rects))
+        self.play(OldLaggedStart(ShowCreationThenDestruction, cw_label_rects))
         self.wait()
         self.play(
             FadeIn(term_rect),
@@ -4156,7 +4156,7 @@ class HowThisArgumentRequiresCommunitingLimits(PiCreatureScene):
                 look_at_arg=factors,
             ),
             morty.change, "pondering", factors,
-            LaggedStart(FadeIn, factors),
+            OldLaggedStart(FadeIn, factors),
         )
         self.wait()
         self.play(
@@ -4165,8 +4165,8 @@ class HowThisArgumentRequiresCommunitingLimits(PiCreatureScene):
         )
         self.wait()
         self.play(
-            LaggedStart(GrowArrow, fraction_limit_arrows),
-            LaggedStart(
+            OldLaggedStart(GrowArrow, fraction_limit_arrows),
+            OldLaggedStart(
                 FadeInAndShiftFromDirection, fraction_limits,
                 direction=UP
             ),
@@ -4175,7 +4175,7 @@ class HowThisArgumentRequiresCommunitingLimits(PiCreatureScene):
         )
         self.wait()
         self.play(
-            LaggedStart(FadeIn, mult_signs),
+            OldLaggedStart(FadeIn, mult_signs),
             FadeIn(lower_equals),
             mathy.change, "sassy",
         )
@@ -4323,12 +4323,12 @@ class NonCommunitingLimitsExample(Scene):
 
         self.add(rows)
         self.wait()
-        self.play(LaggedStart(ShowCreation, row_rects))
+        self.play(OldLaggedStart(ShowCreation, row_rects))
         self.wait(2)
         row_products_iter = iter(row_products)
         self.play(
-            LaggedStart(Write, row_arrows),
-            LaggedStart(
+            OldLaggedStart(Write, row_arrows),
+            OldLaggedStart(
                 ReplacementTransform, rows[:-1].copy(),
                 lambda r: (r, next(row_products_iter))
             )
@@ -4338,13 +4338,13 @@ class NonCommunitingLimitsExample(Scene):
         self.play(Write(row_product_limit))
         self.wait()
 
-        self.play(LaggedStart(FadeOut, row_rects))
-        self.play(LaggedStart(FadeIn, column_rects))
+        self.play(OldLaggedStart(FadeOut, row_rects))
+        self.play(OldLaggedStart(FadeIn, column_rects))
         self.wait()
         column_limit_iter = iter(column_limits)
         self.play(
-            LaggedStart(Write, column_arrows),
-            LaggedStart(
+            OldLaggedStart(Write, column_arrows),
+            OldLaggedStart(
                 ReplacementTransform, columns.copy(),
                 lambda c: (c, next(column_limit_iter))
             )
@@ -4440,8 +4440,8 @@ class DelicacyInIntermixingSeries(Scene):
 
         # Show initial products
         self.play(
-            LaggedStart(FadeIn, top_product),
-            LaggedStart(FadeIn, bottom_product),
+            OldLaggedStart(FadeIn, top_product),
+            OldLaggedStart(FadeIn, bottom_product),
         )
         self.wait()
         for product in products:
@@ -4510,7 +4510,7 @@ class DelicacyInIntermixingSeries(Scene):
 
         self.play(
             FadeOut(q_marks),
-            LaggedStart(
+            OldLaggedStart(
                 MoveToTarget, movers1,
                 run_time=5,
                 lag_ratio=0.2,
@@ -4526,7 +4526,7 @@ class DelicacyInIntermixingSeries(Scene):
         self.wait()
         self.play(Blink(randy))
         self.wait()
-        self.play(LaggedStart(
+        self.play(OldLaggedStart(
             Transform, movers2,
             lambda m: (m, m.final_position),
             run_time=3,
@@ -4645,7 +4645,7 @@ class KeeperAndSailorForSineProduct(KeeperAndSailor):
 
         self.play(
             ShowCreation(sailor_dp_rect),
-            LaggedStart(ShowCreation, sailor_lines),
+            OldLaggedStart(ShowCreation, sailor_lines),
         )
         self.wait()
         self.play(ShowCreation(two_cross))
@@ -4662,7 +4662,7 @@ class KeeperAndSailorForSineProduct(KeeperAndSailor):
             )
         )
         self.wait()
-        self.play(LaggedStart(FadeOut, VGroup(
+        self.play(OldLaggedStart(FadeOut, VGroup(
             sailor_lines, sailor_dp_rect, two_group
         )))
 
@@ -4707,7 +4707,7 @@ class KeeperAndSailorForSineProduct(KeeperAndSailor):
         )
         fraction_words.target.next_to(fraction_brace.target, LEFT, SMALL_BUFF)
 
-        self.play(LaggedStart(FadeIn, group))
+        self.play(OldLaggedStart(FadeIn, group))
         self.grow_circle_and_N(
             added_anims=[
                 MoveToTarget(fraction_brace),
@@ -4785,9 +4785,9 @@ class KeeperAndSailorForSineProduct(KeeperAndSailor):
         product_lines.set_color(YELLOW)
 
         self.play(
-            LaggedStart(FadeIn, fractions),
+            OldLaggedStart(FadeIn, fractions),
             *[
-                LaggedStart(
+                OldLaggedStart(
                     FadeIn, VGroup(*list(lines[-10:]) + list(lines[1:10])),
                     rate_func=there_and_back,
                     remover=True,
@@ -4799,12 +4799,12 @@ class KeeperAndSailorForSineProduct(KeeperAndSailor):
         )
         self.wait()
         self.play(
-            LaggedStart(GrowArrow, limit_arrows),
-            LaggedStart(
+            OldLaggedStart(GrowArrow, limit_arrows),
+            OldLaggedStart(
                 FadeInAndShiftFromDirection, limits,
                 lambda m: (m, UP),
             ),
-            LaggedStart(FadeIn, dots)
+            OldLaggedStart(FadeIn, dots)
         )
         self.wait()
         self.play(
@@ -4882,7 +4882,7 @@ class KeeperAndSailorForSineProduct(KeeperAndSailor):
             pair.target[1].move_to(pair[0], DOWN)
 
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 MoveToTarget, pairs,
                 path_arc=180 * DEGREES,
                 run_time=3,
@@ -4948,7 +4948,7 @@ class KeeperAndSailorForSineProduct(KeeperAndSailor):
 
         self.play(
             ShowCreation(rect),
-            LaggedStart(ApplyMethod, pi_creatures, lambda m: (m.restore,))
+            OldLaggedStart(ApplyMethod, pi_creatures, lambda m: (m.restore,))
         )
         for x in range(4):
             self.play(Blink(random.choice(pi_creatures)))
@@ -5012,7 +5012,7 @@ class Conclusion(TeacherStudentsScene):
         euler.next_to(sine_formula, UP)
         self.play(
             FadeIn(euler),
-            LaggedStart(FadeIn, basel_problem),
+            OldLaggedStart(FadeIn, basel_problem),
             self.teacher.change, "happy",
             self.get_student_changes("sassy", "confused", "hesitant")
         )
diff --git a/old_projects/waves.py b/old_projects/waves.py
index a95e202f..4924e81c 100644
--- a/old_projects/waves.py
+++ b/old_projects/waves.py
@@ -592,7 +592,7 @@ class IntroduceElectricField(PiCreatureScene):
         morty = self.pi_creature
         vector_field = self.get_vector_field()
         self.play(
-            LaggedStart(
+            OldLaggedStart(
                 ShowCreation, vector_field, 
                 run_time = 3
             ),
@@ -651,7 +651,7 @@ class IntroduceElectricField(PiCreatureScene):
 
         self.play(
             FadeOut(self.force_vector),
-            LaggedStart(FadeIn, VGroup(*particles[1:]))
+            OldLaggedStart(FadeIn, VGroup(*particles[1:]))
         )
         self.moving_particles = particles
         self.add_foreground_mobjects(self.moving_particles, self.pi_creature)
@@ -740,7 +740,7 @@ class IntroduceMagneticField(IntroduceElectricField, ThreeDScene):
         vector_field = self.get_vector_field()
 
         self.play(
-            LaggedStart(ShowCreation, vector_field, run_time = 3),
+            OldLaggedStart(ShowCreation, vector_field, run_time = 3),
             Animation(self.title)
         )
         self.wait()
@@ -1033,7 +1033,7 @@ class ListRelevantWaveIdeas(TeacherStudentsScene):
         )
         self.change_student_modes(
             *["pondering"]*3,
-            added_anims = [LaggedStart(
+            added_anims = [OldLaggedStart(
                 FadeIn, topics,
                 run_time = 3
             )],
@@ -1461,7 +1461,7 @@ class ShowVectorEquation(Scene):
         self.play(*list(map(Write, [right_ket, plus, up_ket])), run_time = 1)
         self.play(
             Write(kets_word),
-            LaggedStart(ShowCreation, arrows, lag_ratio = 0.7),
+            OldLaggedStart(ShowCreation, arrows, lag_ratio = 0.7),
             run_time = 2,
         )
         self.wait()