New To The Wiki?
If you are new it is required for you to read the Rules and Guidelines before contributing to our Wiki. If there is anything you need help with, contact an Admin on this list.

And if you see something on this site that is yours and you are unhappy with its presence here, please contact Alphasaith with a link to the page that steals from you and a link to the proof of this being your work.
Also, check out this fantastically sarcastic post by WikiP here.

Heya, we have a great assortment of AUs and welcome everyone, but, if you decide you want to vandalize pages or harass/insult any users, then we highly recommend leaving, as we don't accept that behavior here.

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

There are currently 1,592 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 Undertale Ideas AU 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".

Latest activity

Which is your favorite Self-Insert AU?

The poll was created at 17:15 on September 19, 2017, and so far 16 people voted.

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