NOTE: WHEN UNDERFELL SANS IS TALKING, THE TEXT MAY GLITCH IN FULL SCREEN. BE WARNED P.S. frisk can't be killed. Ever wanted to be Underfell Sans? To see how it feels to give Frisk a bad time? Well now you can! Z to Scroll through text, Left, Right, Up, and Down to Make bone walls. (Press Left, Right, Up, and Down with Space to throw around Frisk's SOUL) E to use "Gaster Blaster." M to make her mortal. O to speak. R to tell something for some reason.
Credits to Nightmarionnette22 and snowthefox