Storyshift is an Undertale AU created by voltrathelively on Reddit. Like Underswap, it involves some characters changing places role-wise with others while keeping their original personalities. What makes Storyshift unique, though, is that the characters are "shifted" in pairs into other pairs' roles, as opposed to with each other, such as Sans having Asgore's role and Papyrus having Toriel's role, while still keeping their original personalities, and relationships intact.