* AlternateCharacterInterpretation:
** The inclusion of the 1987 universe. Was it there to make the special a love letter to Turtles fandom in general by showing multiple generations working together, or a [[StrawLoser ploy by the producers of the 2003 Turtles to make their ''own'' show look good by showing how much sillier everything was in the 1987 universe by comparison]]? (That is, everything except [[UnacceptableTargets 1987 Splinter]]...)
** Similar to the above: Was the Mirage Turtles' CurbStompBattle of the other teams included as a commentary on [[FirstInstallmentWins how superior the original Turtles were]] compared to subsequent adaptations?
* BigLippedAlligatorMoment: When the 1987 and 2003 Turtles visit the 1987 universe for the first time, they witness the 1987 Turtles getting into a battle with a giant mutant banana, pizza monsters, evil leprechauns, and monstrous bowling balls, saving 1987 April in the process. After this scene, the Turtles leave, and 1987 April is abducted by the mutant banana, [[WhatHappenedToTheMouse never to be seen or referenced in the movie again.]]
* BrokenBase: Apparently, the movie's treatment of the 1987-verse divided some of the older show's fanbase. For instance, Creator/DougWalker liked the movie enough that he threw out the {{caustic|Critic}} [[WebVideo/TheNostalgiaCritic Critic]] persona and praised it out-of-character; by contrast, Walker's fellow reviewer WebVideo/{{Phelous}} was one of the few internet critics to give it an overwhelmingly negative review.
** Not so much negative he did enjoy some aspects of it. But being a fan of the 80's Turtles, he wasn't pleased that they were treated so childishly. Doug Walker's brother Rob had a more negative opinion of ''Turtles Forever'' when it came up in a later video about the Ninja Turtle movies, being of the opinion that the creators made the 80's Turtles look stupid because they were insecure about their own show.
* CharacterRerailment: Hun's characterization becomes more in line with his pre-''Back To The Sewers'' version, downplaying the comedy (although not completely removing it) to bring back his ruthlessness and combat-effectiveness. He does lose a lot of the independence he'd developed in the fourth and fifth seasons, though he gets over it after being abandoned by the Shredder again.
* CompleteMonster: [[WesternAnimation/TeenageMutantNinjaTurtles2003 Ch'Rell]] is eventually freed by an [[WesternAnimation/TeenageMutantNinjaTurtles1987 alternate world counterpart]]. [[UngratefulBastard Taking control of the Technodrome from his saviors]], Shredder learns of TheMultiverse and [[VillainousBreakdown goes mad]] at learning of other Ninja Turtles. He decides to find the [[ComicBook/TeenageMutantNinjaTurtlesMirage Prime Universe]] to kill those Turtles, believing that will erase all Turtles from existence. His assault on that universe world [[OmnicidalManiac erase all others from existence]], but he [[LackOfEmpathy does not care that this would include his own daughter]]. Upon learning their deaths will mean his own destruction, [[RevengeBeforeReason he decides his revenge is more important]]. [[ItsAllAboutMe Egotistical]], [[TheSociopath sociopathic]], and power-hungry, Shredder valued conquest and revenge enough that not even risking the end of life itself would stop him.
* FunnyAneurysmMoment: "Another fine mess you've gotten us into." Krang, you don't know how accurate you are.
* HeartwarmingInHindsight: Raph and Leo's brief conversation with the Splinter from the 80's cartoon has a whole new meaning when you remember that that Splinter ''is'' Hamato Yoshi.
* HilariousInHindsight: Mirage Leo's narration works even better as a parody of Frank Miller's work [[ComicBook/AllStarBatmanAndRobinTheBoyWonder now]] than in the late 80's.
** In one of the interviews, Peter Laird mentions he had no intention of the Shredder becoming the "Darth Vader" of the franchise.
* HoYay: 1987 Shredder when describing Ch'rell, and later Krang's little comment when they located him... it's in the tone of their ''voices''.
* MoralEventHorizon: 2003 Shredder does it again, as he [[spoiler:callously attempts to murder the Turtles by using them to pinpoint Turtle Prime. Granted, he's tried to kill them hundreds of times before... but not while Splinter was ''watching them die'', yes, the other Shredders have attempted this, but there was no real sign of a DeusExMachina, ChekhovsGun, or really anything this time that could save them except somebody from the outside, this is what gets Karai to ''finally'' switch sides for good.]]
* NightmareFuel: 2003 Shredder's plan. Destroy the entire universe? Watch as the entire world erases itself, everyone in it and any loved ones you may have before being erased yourself? Pretty frightening.
** There were a few other examples, such as [[spoiler: Hun's quote]] in one scene.
-->[[spoiler: Hun]]: [[spoiler: Yes... Mutation, it's a real ''horror show''.]]
** In-story example: the Mirage Turtles were this to the 1987 Turtles, who were so afraid of their "willing to kill, dismember your body parts and do it with a smile" counterparts that they dropped their weapons and fled. Hell, even Ch'rell was afraid of them when they got up-close and personal.
* OneSceneWonder: [[Film/TeenageMutantNinjaTurtlesIITheSecretOfTheOoze Tokka and Rahzar.]] Also, TheMultiverse slideshow.
* SacredCow: Despite the complete {{Flanderization}} of the '87 cast, Splinter was the only character who was kept faithful to his original portrayal.
* TheScrappy: The '87 Turtles are almost unwatchable to fans of the original series, due to [[TookALevelInDumbass Taking a Level in Dumbass]], taking nothing seriously, and [[TheOtherDarrin not retaining their original voice actors]].
* SuspiciouslySimilarSong: 4Kids couldn't get the rights to the music from the '87 series, so they came up with replacements.
** The '87 Turtles get a new leitmotif that sounds vaguely similar to their theme song.
** [[http://www.youtube.com/watch?v=aLxiIr1ktYY#t=484s The music that briefly plays]] while '87 Shredder scans for Ch'rell sounds a LOT like the [[http://www.youtube.com/watch?v=CZStwGZtF4w Technodrome music]] from the '87 series.
* TearJerker:
** 2003 Raphael and Leonardo's conversation with the 1987 Splinter.
*** ''Especially'' in the Uncut version, because that scene references a (deleted from the original) scene where the 2003 Splinter voiced similar sentiments. It seems that no matter where in the Multiverse you go, Splinter is always a rock of stability and calm for the turtles.
** Seeing the supporting cast of the 2003 series being erased, along with their world.
* VillainDecay: This Trope was inverted for threats from the 2003 such as Hun, who [[spoiler:mutated into a Turtle monster, while this condition isn't exactly ''liked'', he actually becomes much more powerful, so powerful, in fact, that ''none of the Turtles can defeat him''.]]
** Played ''very'' straight with Shredder and Krang, who went from goofy but somewhat menacing in the '87 show to entirely useless here.
*** Justified in that they're nothing compared to [[EvilerThanThou the Utrom Shredder]]... Although given that they had access to the Super Technodrome after the end and were still planning to use ''a giggle ray'' to attack kinda implied that they're still decayed.

----