WARNING! This fight is... scary if you're like 12. If you aren't good with disturbing imagery, this fight isn't for you. STORY! This fight takes place in the genocide after you've killed Papyrus. You were wandering about Snowdin when you came across... this thing... After you had murdered Papyrus, he wasn't ready to die. He tried to bring himself back with DETERMINATION, when we wasn't meant to. This lead to the game becoming corrupt and leaving the player trapped in a black void until the glitch has been destroyed.
I used my battle engine to make this as a way to show you how easy it was to create a fight and the possibilities that could come out from it. This took me about an hour and a half to make using my engine! Make your own fight here: https://scratch.mit.edu/projects/143621938/ Acting in this fight is important. You can heal by doing it and get items.