Consuming Ferocity (MIR)

Enchantment — Aura

Enchant non-Wall creature Enchanted creature gets +1/+0. At the beginning of your upkeep, put a +1/+0 counter on enchanted creature. If that creature has three or more +1/+0 counters on it, it deals damage equal to its power to its controller, then destroy that creature and it can't be regenerated.