Kagemaro, First to Suffer

Description

Kagemaro, First to Suffer (SOK-73) is a legendary Demon Spirit creature from Saviors of Kamigawa. Its power and toughness are each equal to the number of cards in your hand, and you can pay {B} and sacrifice it to give all creatures -X/-X until end of turn, where X is that same hand-size. This makes it a hand-size dependent threat that can function as a board sweeper or finishing play based on your current hand size.