Differentopic is a crossover Undertale AU where characters from various different franchises and YouTube channels replace Undertale characters.

 Character Changes

Main characters


  • Napstablook's role is taken by Casper the Friendly Ghost from the theatrical animated cartoon series of the same name.
  • Mad Dummy's role is taken by Stretch from Casper the Friendly Ghost.
  • Muffet's role is taken by Muselk, a YouTube gamer.
  • So Sorry's role is taken by Tony the Talking Clock from Don't Hug Me I'm Scared.

Random encounters

  • Froggit's role is taken by a Goomba from Paper Mario.
  • Whimsun's role is taken by a Buzz Bomber from Sonic the Hedgehog.
  • Vulkin's role is taken by Tiny Box Tim from Markiplier's videos.


  • Differentopic is now MegaloSans, as Execution became more popular than the AU itself.[4]


  1. I own Differentopic now - SoundCloud
  2. i co-own differentopic now + more fun updates (read desc.) - SoundCloud
  3. New Undertale AU: Differentopic - DeviantArt
  4. Differentopic is now MegaloSans - SoundCloud