The weirdest version of undertale so far and sans fanboys will love it since sans is the king of the monsters (He is heavy).
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Gaster: Storyshift has my son as a king...
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Outertale: Undertale but in space, duh.
Horrortale: Undertale as a horror story.
Mafiatale: Undertale as a cowboy story.
Glitchtale: Undertale as an anime story.
Underpants: Undertale as a fun sitcom.
Underfresh: Undertale for the hippies.
Fanfictales: Generic undertale worlds.
Batter's World: The setting of the game 'OFF' when the batter goes on a quest to purify the world. It was revealed to be a wacky test world created by W.D. gaster.
* Notes: Crossover worlds don't exist. *
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There are many minor undertale worlds.
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The biggest part of the fun earthbound multiverse. It is a multiverse within an other multiverse since it contains many alternate realities with different worlds.
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The undertale multiverse is so much big.
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A simple alternate universe of undertale where the role of all the characters are swapped thus making it very weird and fun to play. It defies the logic of gaming.
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Alfred: Hey, do u know about underswap?
Larry: That game is an insult to logic.
Alfred: Alright, screw off normie bastard.
You don't know what exactly an au is.
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The edgy version of the hit classic game undertale which involves some changes to the story as flowey is kind in the story.
The human stays in the underground as the adopted child of the king in the true ending after defeating their final boss.
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Abby: Underfell has a sans with a gold tooth. No further infromation about it.
Sandy: Aw, that is very sad indeed.
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