mariovsluigi666 asks do you know about AU's

(Author): Well I know really only about Underfell and Underswap. So yeah.

Frisk: I know about a few. After resetting a few times I accidentally fell into the world of Underswap. It was really werid.

Sans: Well I know about a lot of them. Countless of them. I visit the other Sanses from the AU's every once and a while.