Crucio Cruciatus

Target creature get -1/-1. At the begginning of target creature's owner, put another -1/-1 on that creature. Crucio is indestructible. When target creature dies, return Crucio Cruciatus to your hand
Neville: Th-there's um... the Cruciatus Curse. Professor Moody: Correct! Correct! Particularly nasty.