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Undertale AU Wiki
Welcome to the biggest encyclopedia on Undertale AUs.

There are currently 1,213 pages to the site, you can add more!

Check out our sister Wikis! There is the Undertale OC Wiki, as well as the UTAU Wiki RP Wiki, for doing your roleplays. And there is also the UTAU Ideas Wiki, the UTAU Self Insert AUs Wiki, and the Offspring Wiki.

This site contains spoilers for Undertale. if you have not completed the game, you may get spoiled.

  • Alternate UniversesGo to Category:AUs
  • LocationsGo to Category:Locations
  • CharactersGo to Category:Characters
  • ItemsGo to Category:Items
  • MusicGo to Category:Music
  • StoriesGo to Category:Stories
About Undertale AUs
Undertale Alternate Universes, or "AUs", are alterations to the story, world, and or characters of Undertale, be it crossovers, changes in aesthetic, or role-swaps.

"AU" is an umbrella term that includes "ATs".

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Poll is closed down for now. Do not worry, it will be back.

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