* AbandonShipping: Back when the show first started there was a lot of support for Donnie/April. This was due to many people finding Donnie's crush endearing and him being a borderline woobie. However near the middle of the first season he went from attention seeking to what can be considered down right [[StalkerWithACrush stalking.]] This is the first thing that caused people to jump ship. Then near the end of season one he starts making increasingly [[TookALevelInDumbass stupid]] [[LoveMakesYouDumb decisions.]] Que more people jumping ship. Then there's the fact that whenever April [[ADayInTheLimeLight gets an episode for herself]] Donnie's crush [[StrangledByTheRedString comes to the forefront]] when said [[TheyWastedAPerfectlyGoodPlot episode]] could [[TheyWastedAPerfectlyGoodCharacter have taken a lot of time to develop her character.]] This caused EVEN more people to jump ship. To make things worse in season two Donnie has a rather [[DependingOnTheWriter inconsistent]] [[ItsAllAboutMe its all about me attitude.]] (Which only seems to be around when [[DerailingLoveInterests April shows up.]])
** The ship is almost completely abandoned now that [[DarkIsNotEvil Casey]] [[BloodKnight Jones]] has showed up. Due to A.) Being April's [[OneTruePairing most consistent love interest in the franchise.]] B.) [[RescuedFromTheScrappyHeap Becoming]] a [[EnsembleDarkhorse fan favorite]] within a few episodes. ([[DieForOurShip Even by many Donnie/April fans who once wished for his death.]]) C.) Seemingly having [[HiddenDepths having more to him than you'd think upon first meeting,]] and D.) has much more natural [[UnresolvedSexualTension chemistry with April than Donnie does]], seeming to like April for who she is instead of [[LovingAShadow the idealized beauty Donnie loves.]]
* AlasPoorScrappy: When the Pulverizer [[spoiler: mutates into Mutagen Man.]]
* AngstWhatAngst: [[spoiler: Bradford likes his mutation into Rahzar despite it being much more horrific looking than his Dog Pound mutation, since it allowed him to regain some of his ninja speed.]]
* {{Anvilicious}}: The moral about not letting insults get to you, to the point where Raph is blatantly portrayed as putting his "insult ignoring training" to "good use".
* AwesomeArt: The show is one of Nick's better animated CGI cartoons. The acute eye will notice subtle "blink and you'll miss it" moments about the body language of the characters and facial expressions that really help set the mood for certain scenes. The occasional 2D elements that get thrown in every so often make the show visually fun to look at.
** Then there's the fight scenes. They flow well, feel realistic, and can be both fun and exciting to watch. One of the best examples would be [[spoiler: Splinter and Shredder's fight]] at the end if season one.
* BaseBreaker: Either Michelangelo is funnier than ever, or he's more annoying than ever.
** Casey Jones, even before he appeared in the show!
** Donatello. You either think his crush on April is cute or {{Squick}}.
** April's being [[spoiler:angry with the Turtles after they accidentally mutated her dad]] has caused either people to turn against her or explain why she's justified in acting that way. Might calm down after "Target: April O' Neil", where [[spoiler:she apologizes to the Turtles for acting like they did it on purpose and apologizing for the way she's acted to them]].
* BigLippedAlligatorMoment: A mildly disturbing occurs in Fungus Humongus: After Leo gets sprayed with spore and starts seeing his fear, we're all treated to a random scene of all the mushrooms dancing to the Nutcracker Suite. However, it does break the tension briefly of one of the more disturbing episodes.
** Also the cheese phone from The Manhattan Project.
* BrokenBase:
** People either love the new personalities for the Turtles, or think it's crap.
*** Broadly speaking, their personalities still line up with both previous shows' [[ExpositoryThemeTune theme songs]]. The biggest change is Donatello having a crush on young teen April (and Raphael is somewhere between the 1987 and 2003 shows on the anger scale).
** The quality of this version of the turtles is arguably the most divided when it comes to the fans reactions of the whole franchise.
** The [[DivergentCharacterEvolution reworked designs]] of the Turtles seem to be something of a point of contention among a few fans.
** Fans are also divided over whether or not it is a good thing that [[spoiler:Spike became Slash]].
* CargoShip: As per usual fans jokingly ship the turtles with their [[WeaponofChoice weapons of choice.]] However this series has provided multiple new ones.
** Splinter+The empty broken mutagen canister Mikey called "mom."
** Raph+Wooden Spoon
** Leo+Karai's throwing knife.
** Donnie+Metalhead.
** Mikey+Smoke bombs.
* CharacterRerailment: [[spoiler:One of the most consistent problems that were had with ''WesternAnimation/TurtlesForever'' was the CharacterExaggeration the 1987 Turtles went through, save particular quirks, where they were portrayed as being a bit ''[[DenserAndWackier too]]'' silly and too similar. Their brief appearances in "The Manhattan Project" dial back the silliness and uses the characterizations more common to the 1987 series.]]
* ContinuityLockOut: The first season alone demonstrates this, due to the fact that episodes build on each other, lack of PreviouslyOn segments (though the opener may explain), and not really explaining things as well as they could for viewers who have missed an episode or are just starting (though Nick.com is kind enough to leave episodes up for a few weeks just in case viewers missed them).
* CrackShip: Donatello/April shippers and Casey/April shippers have been at each other's throats since the first episode. Those who have been annoyed by their behavior have started shipping Casey/Donatello to troll them for their irrational behavior.
* CreepyAwesome: The Rat King.
* DieForOurShip: Casey Jones has been hit with this by many April/Donatello shippers.
** This reaches into Fandumb territory as some April/Donnie shippers have declared the show of losing "quality" and have declared they will not watch it anymore... simply for the ship teasing of the (almost always canon) Casey/April ship.
* EarWorm: The theme song; seems to be a tradition in the TMNT franchise.
* EnsembleDarkhorse:
** This show's version of Karai has developed a following. Her loyalty to the Shredder/Foot is downplayed, her [[DeadpanSnarker snarks]] are hilarious, and her ShipTease with [[DatingCatwoman Leo]] helps (or [[{{Squick}} doesn't]]).
** Xever/Fishface is slightly more popular than his partner Chris Bradford/Dogpound, due in part to having a more [[DanceBattler visually appealing, unique fighting style]]. It probably helps that the audience learns far more about him than they've learned about his partner.
** Spike and Murakami.
** Despite starting out as TheScrappy (mostly due to shipping), Casey has since become a fan favorite.
** Out of the four turtles Raphael seems to be the favorite. Possibly due to his HiddenDepths.
** Starting out as divided when people found out about the character [[spoiler:Slash]] is now very well liked due to being portrayed as a cunning, genuine threat who provides interesting tension with [[spoiler:Raphael]].
* FamilyUnfriendlyAesop:
** In "New Friend, Old Enemy", Splinter teaches Leonardo that victory is more important than fairness. Granted, he's talking about fighting (potentially) ''to the death'', but perhaps they should have clarified that to the kids watching.
** From Episode 5:
--->'''Splinter''': The first rule of being a ninja is, [[MartialPacifist "Do no harm."]] [[BrokenAesop Unless you mean to do harm.]] [[FamilyUnfriendlyAesop Then do]] ''[[FamilyUnfriendlyAesop lots]]'' [[FamilyUnfriendlyAesop of harm.]]
** ''New Girl in Town'' has Splinter deliver a message to Leonardo that leadership is a hard, thankless task, and he should not think otherwise.
* FanDumb: The endless deluge of hate Casey received from Donnie/April shippers ''before he even appeared'', solely for interrupting their pairing, reached ludicrous levels, and some reactions to his appearance on the show have proven fairly ridiculous as well. Donny/April fans have derided Casey for his [[http://tmntconfessions.tumblr.com/post/70433903717 "creepy" behavior toward April]] (Conveniently forgetting Donny's StalkerWithACrush antics), insisted that Casey is a player who won't take a [[http://tmntconfessions.tumblr.com/post/70531544515 relationship with April seriously]], and decided that he doesn't look like the right [[http://tmntconfessions.tumblr.com/post/60762858130 "type"]] to have a crush on April.
** Others have objected to Casey's presence with the claim that he will [[http://tmntconfessions.tumblr.com/post/62225674190 "mess up"]] the turtles' relationships with each other. Apparently, some are unaware that Casey has been consistently depicted as being a friend of all the turtles, not just Raph specifically, when he appears.
* FoeYay: Leo and Karai. April and Raphael clearly do not approve of this development.
** April and Karai have some too. "Miss me, princess?"
** [[spoiler:Slash]] and Raphael almost have shades of this too, particularly since the former is ''completely obsessed'' [[WeCanRuleTogether with getting Raphael on his side]], and wants to [[MurderTheHypotenuse kill all of Raph's brothers so that he can have Raph for himself]].
* FountainOfMemes: Suprisingly enough this version of Raphael has been the source of most of the show's memes.
* GeniusBonus[=/=]FridgeBrilliance: In Episode 13, the Rat King wears an outfit nearly identical to the ones worn by medieval [[PlagueDoctor Plague doctors]] (long black coat and black wide-brimmed hat). The Bubonic plague was spread (partly) because of fleas being carried by ''rats''.
** In Leatherhead's first episode,he grabs one of the turtles and starts spinning. A grab-and-roll is a tactic used by real life alligators to take down their prey.
* GrowingTheBeard: The tone of the show became more focused and consistent mid-first season, starting with "The Gauntlet", the arcs that were previously only hinted at or set up became more prominent, and mostly dropped the MonsterOfTheWeek format. Later in Season 1, Karai's introduction upshot an interesting dynamic with Leonardo, some new and interesting setpieces were introduced, and the fight scenes and animation [[ArtEvolution becoming far more consistent and fluid]]. Season 2 seems to be helping it along as well, due to heading into a [[DarkerAndEdgier somewhat darker]] direction.
* HarsherInHindsight: At the beginning of ''Rise of the Turtles Part 2'', Mikey wants to drink some mutagen, but Don points out that it may turn him into a pile of goo. Fast forward to ''The Pulverizer Returns''....
** Also fast forward to ''Mikey Gets Shellacne'' where we see what happens when Mikey ''does'' use more mutagen on himself.
** Any moment between [[spoiler: Raphael and his pet turtle, Spike,]] become this after [[spoiler: Spike mutates into Slash.]]
* HeReallyCanAct: While CoreyFeldman isn't a ''bad'' actor, nobody expected how intimidating he was as Slash.
* HilariousInHindsight: Donatello/April and Leonardo/Karai were both [[{{Shipping}} ships]] that only received mere [[ShipTease teasing]] in the ''[[WesternAnimation/TeenageMutantNinjaTurtles2003 2003 series]]'' rather than anything serious. This series takes those teases and makes them officially acknowledged in-universe.
** Donatello and Casey's friendly rivalry and name calling in the ''[[Film/TeenageMutantNinjaTurtles 1990 film]]'', all of a sudden becomes a lot funnier now that the two have received DieForOurShip between those who pair them with April in this series.
* HoYay: Mikey and Leatherhead in "It Came From The Depths".
** Irma seems to be just as jealous of Casey and possessive of April as Donnie is.
* ItsTheSameSoItSucks: Though most of the fandom welcomed it with open arms, a certain minority did not approve of Raph and Casey once again being HeterosexualLifePartners.
* JerkassWoobie: Raph in Cockroach Terminator. Raph shows that he's clearly afraid of regular cockroaches, but then he has to put up with a mutant cockroach and the other turtles are absolutely no help since they either make fun of him or don't give him any sympathy.
** Happens to him again in season 2 [[spoiler: when Spike becomes Slash, hurts his brothers, and has to fight him. The ending where Raph is looking at a chewed up leaf really sends the message that his best friend is gone and has turned into a monster]].
** [[spoiler: As of the season finale, Karai now qualifies, as she is actually Splinter's daughter and has been lied to her whole life by Shredder, and she ''still'' thinks that Splinter's the one who killed her mother and wants vengeance.]]
*** [[spoiler: The ending of Wormquake/The Manhattan Project shows her eavesdropping on the heroes, where April is in disbelief that Karai's actually Splinter's daughter. Splinter states that Karai might believe the truth one day, but its ultimately her decision.]]
** Arguably [[spoiler:Spike, while he did try and murder the turtles he genuinely believed he was helping Raph... it's kinda hard NOT to feel bad for him when Raph calls him a monster.]]
* MemeticMutation: Booyakasha!
** That which is the way the Kraang speak has become mutated by that which is known as the Internet into what is known as a meme.
** The term "sadorable" has become extremely popular on Deviantart.
** A certain preview for the two part finale for season one shows the turtles and April having a little dance party. All three dances shown has become a bit memetic. So you know it shows Leo shuffling. Donnie and April, of all dances they could of done, doing the funky chicken. Then Raph's dance, which might be the most memetic of all.
** "[Insert character name here] confirmed for season 2!" (To the point where fans will search for the most obscure characters possible to keep the joke going.) It'll probably die down once season 2 actually comes along though.[[labelnote:explanation]]This originated from the writers announcing that Casey Jones would appear in season two before season one even aired.[[/labelnote]]
** '''''"I NEVER WANT TO SEE YOU AGAIN!!!"'''''[[labelnote:explanation]][[DarkerAndEdgier April to the Turtles after they (accidentally)]] [[{{Deconstruction}} caused her father to become a mutant]].[[/labelnote]]
** Buzz buzz. [[labelnote:explanation]]Michelangelo says this in the first episode of Season 2 when dressed like a butterfly/moth.[[/labelnote]]
** The costumes the turtles (and April) wore in the Halloween game featured on the Nick website. Especially Raph's [[spoiler: fairy princess outfit.]]
** Raphael: KING OF ALL PIGEONS!!![[labelnote:explanation]]In "Follow The Leader", Raphael, using one pigeon, ''[[TheBeastmaster gets an entire flock of them]]'' to help assist in a stealth mission.[[/labelnote]]
** "[X] on your [Y] if you [Z]."
* MemeticSexGod: Thanks to his dance, Raphael is now considered this.
** Karai and April to a much lesser extent.
* MoralEventHorizon: If Shredder killing Splinter's wife and burning his house down or teaming up with the Kraang isn't bad enough, then there's [[spoiler: him kidnapping Splinter's daughter Miwa to raise as his own and naming her Karai (meaning "weapon"), blaming Splinter for murdering her mother, and making Karai hate her biological father.]]
** Spike at first came off as a WellIntentionedExtremist because [[spoiler: Raph was mad at his brothers]]. However, he crossed it when he not only ignored [[spoiler: Raph's pleas to not hurt the other turtles, but went after him too]].
* {{Narm}}: Mikey calling [[spoiler: Kirby "Wing Nut" after he's been mutated into a bat and the turtles are trying to trap him.]] Which is lampshaded by Donnie.
-->'''Donnie''': You are not giving [[spoiler: Mr. O'Neil a monster name!]]
** Slash's fingernails can [[WolverineClaws extend to puncture or slash at his enemies]]. The result isn't as threatening as it is strange.
* NauseaFuel: Mikey's shell acne throughout the whole episode of ''Mikey Gets Shell Acne''.
* NightmareFuel: Fungus Humongus was a disturbing episode and probably viewed with discretion if you're afraid of rats or cockroaches as the visuals (especially with the roaches) can be frightful. Also deals with different fears such as phobias of things or personal dreads of failure as a leader or rejection out of anxiety and guilt.
* NightmareRetardant: While there is a certain paranoia factor to the Kraang, the [[DepartmentOfRedundancyDepartment "place" where they speak]] creates a difficult "place" with the "place" where they are taken in the serious "place".
** Although this ''can'' be made sinister when they want it to: "The turtles must be eliminated from this place, and ''all other places''."
** As horrifying as [[spoiler: the Pulverizer's mutation into Mutagen Man]] is, there's just something hard to take seriously about his high-pitched voice when he screams "It burns!"
** [[spoiler: Kraang Primes's]] voice was this for many people. Perhaps inevitable, considering that they were voiced by Roseanne Barr, who is known as a comedian first and the casting choice [[WTHCastingAgency was considered pretty strange to begin with]].
* OlderThanTheyThink: A few watchers have commented on the apparent "change" for Splinter to train April in martial arts. It's likely most of the commentators are only familiar with her [[WesternAnimation/TeenageMutantNinjaTurtles1987 80s cartoon counterpart]], who was essentially always a DistressedDamsel. Otherwise, they're a few comic series, [[WesternAnimation/TeenageMutantNinjaTurtles2003 one previous animated series]], and [[WesternAnimation/{{TMNT}} a feature film]] late to that development.
* RescuedFromTheScrappyHeap:
** Leonardo tended to get a lot of reactions ranging from apathy to dislike from fans in previous incarnations due to being, what they felt, to be a rather boring character. This incarnation gets a fair amount of like due to the show making an effort to showcase him as still learning to be a leader, as he has just started, and the addition of other characteristics (his love of ''Space Heroes'' and disobeying Splinter a bit more frequently).
** One can now argue Raph has been rescued from the heap after "Operation:Breakout" as he took several [[TookALevelInKindness levels of kindness]] within the episode. A notable example is [[CoolBigBro his behavior towards Mikey]] in the episode. In the beginning he intentionally does something he knows Mikey can't get enough (albiet at the expense of Donnie), his once an episode DopeSlap came off as a warning for Mikey to mind his manners (Mikey basically just called Leo stupid, which visibly made Leo angry) and near the end he laughs at one of Mikey's jokes while [[AffectionateGestureToTheHead patting his head]]. It helps that he has similar [[CoolBigBro behavior]] towards Donnie in the episode. When he finds out that, yes Donnie still has a crush on April he recommends Donnie not involve him, both as something he obviously thought was helpful advice (since he just embarrassed Donnie) and because he was clearly a little angry Donnie was, in a sense, using him. This has unintended consequences as Donnie [[spoiler: leaves without the others on a resque mission for April's dad.]] He obviously felt bad when he realized this and in the end retold the episodes events in a way that made Donnie look like the big hero of the day which [[spoiler: resulted in Donnie getting a hug from April]]. [[RuleOfThree It probably helped even more]] that he was called out by Leo for his negative behavior and then, as stated above, made up for it by the end of the episode.
*** This only furthered when the season 1 finale showed that as long as it isn't [[WhyDidItHaveToBeSnakes a cockroach]] he is [[FriendToAllLivingThings kind, gentle, and even affectionate to non-mutated animals.]]
** Michelangelo is frequently derided for being even dumber than his previous incarnations, but has earned some likability for having occasional moments of competence in episodes like "New Friend, Old Enemy" and "Parasitica".
* RomanticPlotTumor: Almost every episode featuring April in a big role is going to heavily feature Donatello's obsessive crush on her, and it's gotten to the point where many are tired of it, especially now that Casey Jones is in the picture and making it a love triangle.
* TheScrappy: All of the turtles, save for Leo, got into this zone:
** Michelangelo gets this from one side of the BrokenBase, due to feeling the show downplayed his HiddenDepths in favor of making a bigger deal on his humorous side, which results in him being grating due to him [[ComicallyMissingThePoint missing the point]] of usually very high stakes consequences.
*** The hate seems to be magnified a bit with him constantly whining about the Rat King's ''name'' in the latter's debut episode. Aside from the fact that it seems like a TakeThat to a classic character with an established history and fanbase, Michelangelo seems to think he has dibs on how villains should name themselves and would ''not shut up about it for the whole episode.''
** Raphael, due to being a bigger jerk in this series than he's usually depcited, has his fair share of people who dislike him.
** Donnie has landed himself in this by the end of season one. His crush on April was viewed by fans a cute and even endearing during early season one, then suddenly it stopped being referenced to for a few episodes, then it came back but extremely flanderized. More focus starts getting put on it and we get to see [[TheSmartGuy Donnie]] makes less than [[IdiotBall rational]] choices because of it. Then there was Operation: Breakout. Raph tells Donnie to leave him out of his attempts at impress April. (Raph clearly didn't like being used like that and was offering some [[SincerityMode advise he seemed to think was helpful.]] ) So what does Donnie do? He basically goes [[spoiler: on a VERY dangerous rescue mission, [[WhatAnIdiot by himself]], without [[TooDumbToLive telling anybody]], to get April's dad away from the Kranng. Not only that but he almost gets himself and Mr.O'Neal killed multiple times.]] All to impress April.
** Outside of the turtles are the Kraang, as they get this mostly for the fact that once they start talking, they're almost never going to shut up. As time has gone on, the show seems to have tried to phase out the humor aspects, possibly [[RescuedFromTheScrappyHeap saving them]] a little.
** The Pulverizer is quite disliked for being an obnoxious fanboy whose levels of stupidity range from uncanny to mind blowing.
** Spiderbytez, an intentional case, for being a crude, realistically obnoxious person before his mutation, and only got worse upon it. Does(n't) help that grumpy neighbors like him exist and are one IRL.
* SpecialEffectFailure: While the show's CGI is generally fairly good, sometimes an acute eye will spot that there's something off about the skyline or the distant buildings.
* {{Shipping}}: Donnie and April have been getting this since the first episode. Also, people started shipping Leo with Karai as soon as the description for "New Girl in Town" was released (a legacy of the 2003 show).
** Casey didn't appear until Season 2, but he got DieForOurShip from Donnie X April shippers long before his debut.
*** Some fans got so tired of the drama surrounding April, Donnie, and Casey that they disregarded the love triangle completely and began "[[HeterosexualLifePartners bro-shipping]]" Casey and Raph instead.
* ShipsThatPassInTheNight: Casey Jones was being shipped with Karai not just before they ever met, before he even appeared.
* {{Squick}}:
** A birthday cake made out of algae and earthworms.
** Almost everything about the Spy-Roach from [[Recap/TeenageMutantNinjaTurtles2012S1E18CockroachTerminator Cockroach Terminator]].
** In-Universe, [[spoiler:the Turtles reaction to the sea monster guarding the Kraang fortress ''falling in love with their submarine''.]]
** Depending on whether or not you believe the [[spoiler:mutagen made the turtles related to Splinter by blood]] the fact that [[spoiler: Karai is infact Splinter's daughter]] may have very well caused this reaction in some fans. [[spoiler:Especially since Leo had/has a crush on her and Raph admitted she's hot "in the evil way".]]
*** The people who were guessing that [[spoiler:this version of Karai and Splinter are related since]] before the show even aired (due to promotional material) found the [[spoiler:Leo+Karai ship]] gross, especially if they're in the party that [[spoiler:believe the Turtles and Splinter are related thanks to the mutagen]]. The confirmation that [[spoiler:yes, Karai is Splinter's daughter]] has caused several people to [[spoiler:abandon the Leo+Karai ship.]]
** Some fans find any mutant+human shipping to be a bit...odd.
** [[http://24.media.tumblr.com/36406393c13d454ef554e5a362ff5b40/tumblr_ms9f2yM0ew1rd9dsao5_1280.jpg Concept art notes]] on the Mousers reveal that their "gut" carries 5 Rat Carcasses. ''Ew.''
** Wormquake/The Manhattan Project reveals that mutagen comes from [[spoiler: alien worms and the mutagen has to be milked from them.]]
* StopHelpingMe: The turtle's basic reaction to anything "The Pulverizer"/Timothy does to try and be more like them or be useful to them.
* TheyChangedItNowItSucks:
** Believe it or not, the most controversial change is the addition of a third toe on the Turtles. Fans ''exploded.''
** April being de-aged to a teenager hasn't been taken very well. And as of "Monkey Brains," people are complaining about [[spoiler: her "empathic" ability and Splinter's decision to train her in ninjutsu because of it]].
** Neither has the replacement of "Cowabunga!" with "Booyakasha!"
** Karai's [[http://images3.wikia.nocookie.net/__cb20130119004208/tmnt/images/6/69/Turtles_Karai_press_photo.jpg new design.]]
*** Reactions are a bit better now that [[http://images1.wikia.nocookie.net/tmnt/images/d/dd/Karai_pins_Leo.jpg her full appearance has been revealed]].
*** Though the decision to make her [[spoiler: Hamato Yoshi's biological daughter is something that threw fans off. Especially since they saw that plot-twist coming a mile away]].
** Within this particular version, the second season's DarkerAndEdgier turn, [[spoiler:in which April's father becomes a mutant, and as a result now hates the Turtles for causing it to happen, despite the fact that it was an accident.]]
** The revelation that [[spoiler: April is a [[HalfHumanHybrid half-Kraang mutant]] is already starting to turn some people off.]]
* TheyWastedAPerfectlyGoodPlot: April [[YouCantGoHomeAgain being unable to leave the lair]] when both Shredder and the Kraang are after her is never even implied after it comes up, and only lasts for a few episodes.
** Although in Fungus Humongus, she did mention she spent weeks living with them.
* TooCoolToLive: Tiger Claw who even gets a badass death scene [[StarWars similar to another badass bounty hunter]]
* UglyCute:
** The Mousers. They even make cat-like noises!
** Justin.
** Pete.
** This incarnation of Casey, as opposed to being quite attractive in the [[WesternAnimation/TeenageMutantNinjaTurtles2003 previous cartoon]].
** [[spoiler:Slash just may count, having those small, creepy eyes and big jaws and spikes protruding out of his body, but yet you still want to pinch his cheeks, if he has any.]]
** The mutant mushroom's minions. At least from Mikey's point of view.
** The Kraathatrogons, who have ''very'' catlike faces that, when they're annoyed, turn into maws, which somehow doesn't mitigate how strangely ''adorable'' these giant worms are.
* UncannyValley:
** While stylized like everything else in the show, the Kraang's disguises are droll businessmen whose eyes and mouths scarcely move, as if the Kraang are barely trying with their disguises, creating a rather odd and creepy effect.
** Then there's [[spoiler:Mrs. Campbell]], who is also a Kraang creation, and only gets creepier during [[spoiler:her]] fight with the turtles.
** There's something creepy about the realistic lips that [[spoiler:the mutated Pulverizer aka Mutagen Man]] has.
* TheUntwist: Many fans saw the first season finale's twist about Splinter's daughter coming a mile away. The fact that Hamato Yoshi never had a daughter in other continuities [[spoiler: and that in continuities where she was Shredder's daughter, Karai was always explicitly referred to as his ''adopted'' daughter]] is what made it easy to predict.
* WhatAnIdiot: Episode 6. A Kraang takes control of Donnie's robot and the guys futilely attack it, claiming it has to have some sort of weak spot...completely ignoring the Kraang that's just sitting on its head right out there in the open.
** The season 2 premiere has the turtles (except for Donnie) playing dodgeball with the Kraang communication orb. Which Donnie calls them out on. Nothing new for Mikey and Raph, but Leo should've known better. Sure nothing bad came of it but still.
** A better example would be[[spoiler: Mikey telling April that it was their fault that her father became mutated, causing her to hate them]]
** Mikey holds the ball even harder in the "Shellacne" episode, since in order to make himself cooler he exposed himself to dangerous experimental retro-mutagen, missing the fact that Donatello put several warnings of how deadly it was on the can since he only looked at the front.
* WTHCastingAgency: Roseanne Barr being cast as [[spoiler:Kraang Prime]].
** It may well have been intentional casting a comedian considering how ridiculous the Kraang are.
* TheWoobie: Poor, poor Kirby. The guy just can't catch a break.
** April. In season 1, the worst thing that happens to her is her dad getting kidnapped. Things get even worse in season 2.