Krail, Host of the Many

+1: Sacrifice a creature, then put x +1/+1 counters on target creature, where x is the sacrificed creature's mana cost.
-4: Destroy target creature. Creatures you control gain trample till end of turn.
-5: You draw x cards and creatures you control get +x/+x till end of turn, where x is the number of +1/+1 counters on target creature you control.