Mirage

Consuming Ferocity

Play only on a non-Wall creature.
Enchanted creature gets +1/+0.
During your upkeep, put a +1/+0 counter on enchanted creature. At the end of any upkeep, if that creature has three of these counters on it, bury the creature and it deals to its controller an amount of damage equal to its power.

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.