Slimetale Stories

Upon finding a strange necklace floating in a river, Frisk picks it up only to have their memory wiped and was replaced by Dr. Bright. Not knowing who they where, Dr. Bright returns to their village only to be kicked out and was captured by the foundation. The site nearby is an underground facility which not only contains SCPs but monsters as well.

Unlike in the world of Undertale, there was no war but instead the monsters and humans were separated in order to blend in with the other timelines. The monster and human souls contain pieces of an entity. The monsters are able to communicate with the entity and have heard stories of the other AU's. All residents of the AU are a pale blue.