- How about the scene where the Shredder gets decapitated?
- And then he picks his head up and walks away! This is before he's revealed to be an Utrom, so it leaves you shaking in your seat wondering 'what the shell IS he?!'
- 4 words: Insane In the Membrane.
- So much that it was taken off air. For starters, Stockman's new body starts to melt. And blood and flesh are apparently visible, plus we get to see him hitting his own arm with a hammer and a nail. Ewww!
- One of the more subtly creepy moments comes when Stockman kidnaps April, believing her to be to blame for every bad thing that ever happened to him, and drags her back to the lab they used to work at. It's frightening enough to see her being kidnapped by a half-rotted, utterly insane man, but when they reach the lab, he goes nuts again and now thinks that they're still working there, she's still his assistant, and everything that happened to him in the series never happened. Not to mention the fact that, as his mind degrades, he slips into calling April "Mommy". Cue a horrified April watching as Stockman seems completely unaware of his disintegrating body, cheerfully telling her about all the stuff they need to work on today.
- When Bishop got impaled.
- Both Tengu Shredder and Utrom Shredder are outright terrifying in their own right:
- The Bad Future, as shown in Same As It Never Was. The world is a dystopian nightmare, the Shredder has conquered the Utroms and spread his evil across the universe, the Turtles have split up and lost all hope, Splinter and Casey are dead, and April is one of the handful of people still desperately fighting as part of the resistance. By the time the episode is over, EVERYONE except Donnie and April are dead, including Shredder and Karai.
- Shredder's death: Torn in pieces by a sonic drill.
- Ultimate Drako.
- We get to see what happened to the original tenants of the Brotherhood's planet. As in, massive piles of skeletons with flesh eaten clean-off.
- The bone demon's ultimate form in "Fathers and Sons." Good effing God.
- The fates of the people mutated into monsters by the Foot in the "Notes From The Underground" series. They were kidnapped, turned into monsters, imprisoned in glass tubes for awhile, and then escaped. They gradually are going to go insane and turned into mindless monsters. And when they lead the turtles to a forbidden area of the underground, the still-sane ones start disappearing one by one.
- The episode "The Darkness Within", which is basically a Lovecraft Lite story in a kids cartoon. There is a mansion in New York that has been there as long as anyone can remember. One day, Angel, the troubled girl the Turtles saved from joining the Purple Dragons early in the series, tells them that her brother found a gold coin during his construction work in the area, and has been missing for three days after going there to look for more, and asks the Turtles to find him. Turns out the mansion was built on top of an Eldritch Abomination that draws in followers by preying on their greed, and it has been luring in victims to feed on for centuries. The Turtles are trapped in their own nightmares, and when they manage to escape their torment, they find a chamber filled with thousands of skeletal remains, trapped in pods like theirs. Leo manages to kill it with a magic spear, and everyone escapes with their lives. Seems like a happy ending, right? Until a nearby payphone starts ringing, just as a random pedestrian walks by...Voice On the Phone: COME TO ME. SERVE ME AND I WILL GIVE YOU POWER AND WEALTH. *the mans eyes starts to glow red*
- How about the Turtles nightmares? Leonardo dreams that Splinter has turned evil and he accidentally kills him, Mikey dreams that Leo has joined with the Abomination and wants him to follow, and Raph dreams that he comes across the Shredder... only to knock off his helmet, and see his own face underneath.
- Oh, and did we mention that the basement leading to said chamber is inhabited by living, screaming skeletons? That's right, the gateway to the chamber where the abomination lives is teeming with the undead.
- And then there's the fact that there's this old guy living in the mansion that was built on top of said abomination. While he has the decency of being kind to the turtles and Angel, it turns out he's none other than C.F. Vopelhart, who's been continuing to live for centuries since he started letting the creature control him. He's regretted letting it control him, but he hasn't been able to kill it, and now he's relying on the turtles to do the job for him. When they finally do it, he rots away into a skeleton, lets loose one last scream, and crumbles to dust (at least he's happy that he's finally free from the creature's control, of course).
- HOLY FUCK! "Adventures in Turtle Sitting"/"On Good Genes" is full of it:
- For starters, Donnie's leg wound from the mutants created by Stockman and Bishop mutate him into a freaking red eyed prehistoric monster of a turtle. The worse part: IT'S DONNIE THAT'S INFECTED! Meaning that The turtle are forced to get help from not only Leatherhead, but also Bishop and Stockman.
- And when they enter Bishop's base, Donnie breaks free, forcing Leatherhead to fight him. During the fight, Donnie tosses Leatherhead near the operating table, triggering a flashback of the torture that Leatherhead suffered by Bishop. It gives him a nervous breakdown with a monster Donatello hellbent on killing everyone and about to hit Leatherhead from behind. Good thing Leo got there in time to knock Donnie out.
- Not only is Donnie a rampaging monster, but he is dying! Having TWO kinds of mutation is too much for anyone and one has to wonder what kind of pain he is enduring.
- And that is not even the worst part. It turns out that the relic that Bishop wanted was keeping the REAL SHREDDER'S HERALDS chained as Foot mystics, and now that they are free, we all know that lead to. To say that both sides had messed up doesn't even begin describe it.
- The Shredder's eventual fate after the Turtles foil his plans to escape Earth and take his war to the Utroms: He's exiled to an ice asteroid belt in deep space, far from any life-bearing worlds, where he'll remain alone for eternity. Especially chilling since it seems that the Utroms are immortal. An extra layer of nightmare fuel comes up if you notice that the courtroom scene is heavily reminiscent of the Nuremberg Trial. He is freed at the beginning of Turtles Forever, but still.Utrom Jury: May your actions haunt you forever...
- The actions that brought Shredder that punishment. He has spent centuries laying waste to countless worlds in his endless greed and cruelty. Millions have perished under his tyranny.
- Viral's fate in "Tempus Fugit". She was evil and all, but to watch her be ASSIMILATED AND CONSUMED by a backup copy of the Utrom Shredder's personality, pure Body Horror as she's invaded from within, screaming the whole time, was downright horrifying. Not that she didn't deserve it, especially after she blasted Master Splinter into digital bits, but she was practically murdered in one of the most agonizing ways possible for an AI virus to go. And of course, the Cyborg Shredder's laugh as he emerges from Viral's body only adds to the effect.
- Leatherhead's Big Damn Heroes moment in "Bishop's Gambit". Just as the turtles are about to be executed by Bishop's goons, Leatherhead shows up, very angry after the sound wave the soldiers activated agitated him. As the soldiers crap themselves in terror, Leatherhead lunges at the camera, and all we hear after the screen blacks out is the sounds of ripping and screaming. Thankfully, we see no blood in the next scene, but we can only assume he killed them in a very messy fashion.
Nightmare Fuel / Teenage Mutant Ninja Turtles (2003)