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.

It will be released chapter by chapter with a coherent save file between chapters.

About the AU

Primus’ Underfell is vastly different to the fandom’s interpretation. Next to none of the original creator’s designs for the characters are used, and the basis of swapping routes is not present. This Underfell is based around the main premise that after the events that occurred when Chara and Asriel died, Asgore became remorseful and locked himself in New Home for hundreds of years, leaving nobody to rule the Underground. The long-lasting effect of this anarchy sparked a new world of pain and suffering, due to there being no laws to follow and rules could be broken freely because there were no rules. It all took off from there...

No characters changed from the original Undertale, but the world around them changed which causes their personalities, outfits, likes and dislikes to have changed.

Notable Changes

  • Killing still isn't necessary: Spare every monster you possibly can before leaving the area.
  • Or don't spare at all, whichever you want. The story is what you make of it, after all.
  • A character-focused story that spans at least 5 chapters with 5 locations to explore!
  • (Somewhat) Original score bursting with personality and feels. Emphasis on feels.
  • You can still pet a lot of dogs. (There might be a cat somewhere in there.)


  • Primus was previously known as Team Spritedgy and were previously making a much more classicfell game.
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