Thanos

+1: Put 1 counter on an Infinity Gauntlet artifact on the field. If there is not one out, search your deck for it and put it onto the battlefield.
-1: Equip Infinity Gauntlet to Thanos. If it has exactly 6 counters on it, Thanos becomes hexproof and indestructible until your next turn.
-6: Destroy half of all opponents' creatures and planeswalkers.