Altertale is an Undertale role-swap alternate universe by friisans where Sans has swapped bodies[1] with Toriel, Papyrus with Asgore, and Gaster with Asriel. There are no other swapped characters in this AU, meaning only Sans, Papyrus, Toriel, Asgore, Asriel, and Gaster have been altered in this AU. Everything else remains mostly unchanged.[2]

The characters' traits are 20% canon and 80% their role.


Sans Aster

Main article: Sans Aster (Altertale)

Sans Aster[3] is the ruinskeeper and former king of the Underground. He left the throne to go reside in the ruins after his brother betrayed him, and housed all 6 children before they were killed.

Papyrus Aster

Main article: Papyrus Aster (Altertale)

Papyrus Aster is the king of the Underground and responsible for the deaths of the 6 fallen children. He has been burdened with tremendous guilt and deeply wants forgiveness, and to see his brothers again.

Winding Aster

Main article: Winding Aster (Altertale)

Winding Aster[4] (W. D. Gaster) is the late Prince of the Underground and the younger sibling of Sans and Papyrus. He was the first monster since the war to come across a fallen human.

Toriel Dreemurr

Main article: Toriel Dreemurr (Altertale)

Toriel Dreemurr is the lazy sentry of the underground and the first monster Frisk meets outside the ruins. Silly and fun, she helps guide Frisk through Snowdin and her brother’s puzzles.

Asgore Dreemurr

Main article: Asgore Dreemurr (Altertale)

Asgore Dreemurr is a young and charismatic fluffybun who dreams of being in the Royal Guard. He is pure-hearted and kind to everyone.

Asriel Dreemurr

Main article: Asriel Dreemurr (Altertale)

Asriel Dreemurr is a mysterious goatman who used to work under king Papyrus as the royal scientist. He was ripped from existence after falling into the core, and only Toriel and his 3 followers seem to remember him.


  1. "please draw toriel and sans in swapped bodies thank you ily" - Tumblr
  2. What is Altertale? - Tumblr.
  3. "The current rulers of the monster kingdom were a pair of brothers from the Aster family." - sparrowhaven. May 4, 2016. Tumblr.
  4. "As it turned out, Winding learned to talk fairly early." - sparrowhaven. May 4, 2016. Tumblr.