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Nightmare Fuel: Rise of the Guardians
Considering that the villain is the Boogeyman, this isn't surprising. However, in the books, Pitch's main forces are the fearlings - essentially The Heartless. They are also noticeably absent from the movie. At the end of the film, however, Pitch tells Jamie and the Guardians (and Jack) that "there are other ways to snuff out the light". Fearlings were once children from all over the universe - Pitch likely intends to turn Jamie into a fearling. At then end of the movie as well, Pitch lunges at Jamie, only to pass, unseen, through him. Jamie is lucky he avoided a Fate Worse than Death.
The brief glimpse of the expression Jack gets when Pitch breaks his staff. Made especially awful considering he never looks like that at any other point, even after attempting to fight Pitch off and plunging from what appears to be a few hundred stories up. It's easy to imagine that Pitch could have probably made that much worse...
It physically pains Jack when his staff is broken, enough that he can't react when Pitch throws him into the side of a glacier. Yikes, no wonder he never lets go of the thing.
Sandman finally being overpowered by Pitch after a ferocious battle where the two are pretty evenly-matched. Just the look on his face as he's watching himself become consumed by the black sand, and no one can help him. Also doubles as a Tear Jerker towards the end.
In the same scene where Sandy dies, when Jack attacks Pitch's nightmare sand with his ice powers. The resulting collision is HUGE. The camera even pans out to fully see the magnitude of the thing. It alternately doubles as a CMOA.
There's a shot towards the end of the climax in which Pitch's Nightmare sand has formed into a giant wave that is coming from every side, moving towards the heroes and the town like a flood.
Pitch being forcibly dragged, kicking and screaming, back underground by his own fears at the end.
Pitch's lair could be considered Nightmare Fuel in an atmospheric sense. Located in a hole in the ground, it is a drab, dull and colorless environment that is absolutely joyless compared to all the other environments in the film. And Pitch could be lurking in any shadow . . . .
Pitch's lair looks a lot like a Film Noir, considering how colorless and shadowy it is.
Pitch taunting Jack with his memories and in the midst of it, we see numerous shadows of Pitch circling Jack along the walls like sharks.
Jack begging him to stop doesn't help matters, either.
The entire scene in Pitch's lair counts as Nightmare Fuel in and of itself. Jack, our usually flippant, sarcastic and witty hero who always has a comeback, is rendered absolutely terrified by Pitch's Circling MonologueBreak Them by Talking speech, to the point of begging Pitch to stop it. The whole atmosphere is claustrophobic with the circling shark look mentioned above, and Jack being the Audience Surrogate we immediately feel powerless. Not to mention the Fridge Horror that this might actually be how he's felt for the past few centuries in isolation and Pitch is just widening the cracks.
So your brother just saved you from falling through thin ice? That's great! You're safe now! Everything will be fine! Then you watch said older brother fall through himself, know he will drown and die because you can't help him and there's no one else around, and his body is never found because he turns into an invisible winter spirit. Also doubles as a Tear Jerker.
To twist the screw, even if she could not see him, Jack could have written something nice on her window if she had glass, or any liquid filled pot if she didn't. Just a bit a reassurance that he did not blame her. But no message was ever sent, because for unknown reasons, the fairies were unaware of Jack's amnesia. He never got to tell his sister goodbye.
Sure, it may have ended in a bit of a Narm moment since Jack interrupted him with a snowball, but Pitch's Slasher Smile when he's asking Jamie if he believes in the Boogieman is really creepy.
Later, Pitch does it again when he dissolves into shadows and rises up behind Jack about to strike him down with his scythe with that same expression still on his face.
Pitch does a lot of Slasher Smiles throughout the film - it almost gets progressively creepier as he gets stronger.
If you think too hard about it Jack, being the least believeable of Guardians (seriously, everything he does is explained early on to a lot of children by the tilt of the earth's axis and whatnot) is really susceptible to a lack of belief. Tooth loses her flight, Bunny becomes cute, but useless, so what happens to Jack? Does he become a frozen corpse?
North's was probably the worse. He doesn't just lose his powers; he becomes the old man he's supposed to be, completely sapped of his energy and barely being able to get around without using his sword as a cane. It's horrifying and depressing!