Move your soul to avoid the Gaster Blasters by using the arrow keys. Score points by however much HP remains after every round. (The round repeats over and over until you die, but after the first set, both the world high and your score appear.) You can't see HP, making the game harder. You do start with 500 though!
Thanks to @DaBestMarioPlayer for the engine I used for this! Sans, Chara, Gaster Blasters, "Song That might play when you fight Sans", and all the other #Undertale aspects are thanks to Toby Fox.
