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

There are currently 521 articles, 2,893 files, and 35 active users on the site!

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Alternate Universes

The Undertale Alternate Universes of the Multiverse.

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Fanmade Songs by the Community.

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Fanmade Games by the Community.

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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".

Featured Article
Inverted Fate
Inverted Fate - Characters.png

Inverted Fate is an Undertale AU taking place after a failed True Pacifist run. Asriel won the final battle and started to reset time, but lost control of his powers, resulting in the six main characters or "lost souls" swapping places but not personalities. This ends up creating a very different Underground.(more...)

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Latest Blogs
Nobodysans Nobodysans 1 day ago

No-onetale chapter 2

nobodysans asked Sans for a white shirt, bla…

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TheTubeBroke TheTubeBroke 8 days ago


i found this really cool asriel dreemurr god…

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