The Gatewatch

+1: Create a 0/1 green plant creature token, then The Gatewatch deals 1 damage to target creature.
0: Until end of turn, The Gatewatch becomes a 4/4 Human Soldier creature with indestructible, create a 2/2 black Zombie creature token.
-15: Create 15 2/2 black Zombie creature tokens, The Gatewatch deals 15 damage divided as you choose among any number of creatures, you gain 15 life