Nightmare Fuel / Kingdom Hearts: Chain of Memories
That's right folks, a Disney game with the personification of death itself.

  • Castle Oblivion itself. The outside architecture is bizarre and off-putting, the interior design is incongruously stark white despite the castle's abandoned state, and each of the rooms look exactly the same when not altered by map cards. The ominous music in the background intensifies how unsettling the building's design is.
  • Sora slowly losing all of his memories, specifically replacing Kairi — one of his best friends — with Naminé, was rather disturbing. The depth of his brainwashing was made most explicit when Sora begged Naminé to break his heart to save herself, knowing that she'd been manipulating him the entire time and that he'd probably end up catatonic, staring at nothing just like the Riku-Replica.
    • The whole concept of losing one's memories the further into Castle Oblivion they go is pretty heavy Nightmare Fuel all on its own. Sora's gradual descent into madness just makes it even worse.
  • Vexen's death in the manga. We're treated to a glorious two-page spread... of Axel punching a hole through Vexen's chest.
    • Vexen's death in general, which has two other versions. The original GBA version has Axel cutting his throat from behind. The PS2 remake/PS3 HD ReMIX versions have him gloriously burned alive.
  • Zexion's death occurs offscreen in the original version, but in [Re:CoM] we see it in full, with him begging the Replica for his life and slowly going limp, dangling like a hanged man as the life is drained from him.
  • How about that scene where Aerith flat out tells Sora that she doesn't exist? And Goofy and Donald don't see her?
  • Marluxia's third form (pictured above) looks like something straight out of a horror game; the music and the arena we fight that thing in doesn't help either.
  • Oogie Boogie's pre-Boss Battle cutscene, where he drinks the "true memories" potion... and something suddenly gives him the mother of all Oh, Crap! reactions.
    Oogie: Agh! What's this? What... Something's wrong! Something deep inside me. Something...scary!
    Oogie: No! Get back! Stay away from me!