Ajani the Animus

+1: Until end of turn, target creature gets "Whenever it blocks a creature, it deals damage to that creature's controller equal to its power."
0: Ajani the Animus deals damage equal to its loyalty to target creature or player, then remove half the loyalty counters from Ajani (rounded down.)
-9: Put ten +1/+1 counters on target creature. At the beginning of your end step, you win the game if you control a creature with 20 power or more.