just the normal undertale controls, this is the genocide route btw. gaster has just glitched your stats and you need your stats back, so he must die.
Thanks to pococikapusta for Undertale Simple Battle Creator , go play that after this.♎︎♋︎❒︎?♏︎❒︎?︎ ♎︎♋︎❒︎?♏︎❒︎?︎ ⍓︎♏︎⧫︎ ♎︎♋︎❒︎?♏︎❒︎?︎
