Welcome to the Undertale AU Wiki!
Hello! This is a wiki dedicated to the myriad of Alternate Universes for the indie role-playing game UNDERTALE, by Toby Fox.

Alternate Universes, or "AUs", are alterations to the story, world, and or characters of Undertale, be it crossovers, changes in aesthetic, or role-swaps.

The objective of this wiki is to record, document, and feature each AU's contents and ideas, as well as give credit to the AUs and their original creators.

Given the nature of AUs, spoilers for the original Undertale will be present here. It is highly recommended that you've already played the game before reading this wiki.

AU Submission Guidelines
In order to submit an AU to the wiki, it must follow these guidelines:

1.) The AU must have a reasonable amount of content. If it's a drawn comic, sprite comic, and/or written story, it's recommended that at least 2-4 parts/chapters (2 long parts vs 4 short parts) have already been released for public viewing. Alternatively, if there is an abundance of official or fan-made music/artwork for the AU, as well as a relatively descriptive summary of the plot and all major characters, then it may be submitted.

1a.) Please do not submit a page/pages for an AU if you had only created it recently, or are in the process of creating it. Please wait until you finalize the major points of it, as well as producing a reasonable amount of content.

2.) If the AU is not owned by the submitter, then full credit must be given to the original creator(s).

3.) False information regarding an AU, intentional or not, is not allowed. New information regarding an AU and its contents must be fact-checked from the official source.

4.) Low-effort AU characters (copies or recolours of existing characters from Undertale, labelled as "original") are strictly prohibited.

5.) AUs with NSFW/L content must include a warning on the top of their page. NSFW/L imagery is strictly prohibited.

6.) It can't be a combination of two existing AUs. However, it can be a new AU built on the premise of the combination of AUs; specifically, a new AU using the same character roles as a combination of AUs would, but under a different name and with different designs to characters, plot, and other details.

Failure to follow above guidelines when submitting an AU to this wiki will result in the page's deletion or modification. Repeat offences will result in a ban.

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Featured article
Primus's Underfell is an upcoming game by Primus based on their interpretation of the aesthetic AU, Underfell. The general premise of the game is traversing through Underground after being morphed into a much more darker, twisted world than in the original game.


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Undertale Wikis

List of Undertale AUs and Fangames!

UndertaleUndertale AUs

Underfell (Primus) • Underswap (Team Switched) • OutertaleStoryshiftUndertale YellowHorrortale
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