On hiatus. (Takes place after the True Pacifist ending) The barrier has been broken and all the monsters were free from the Underground. Most of the monsters have began to pack for the trip to the surface, but some monsters stayed behind afraid of the discrimination the humans would throw at them. Toriel is one of th...
After Frisk goes missing, Caitlin, Frisk's twin sister goes looking for her in the the last place she saw her. MT Ebott, the mountain of dark legends, she finds a necklace that belonged to Frisk on the ground. Just like Frisk, Caitlin tripped and fell into the Underground. Caitlin finds things she never knew existed.
Chara has the scary ability to jump into savefiles and corrupt them by taking over the fallen child and making them do a 'Genocide Run' When Chara comes across a continuing timeline that has reached the surface but has not yet been reset under the name of 'Frisk', curiosity takes over and they leap into this save file...