My brother ruined me and my bestfriends friendship and she hates me, i NEED to get him severly back..?

How can i prank him terribly, hurt him somethin to get him back? Something evil i can use to physically HURT him. And dont tell me that i should not hurt him, either way its happening. So he told her that i made out with her ex and that she shouldnt be friends with me. This is a LIE. He swears to god an everything that he secretly watched us, no it didnt even happen. So i need the BEST idea to hurt him so bad he crys