The Doom Slayer

Haste, Enrage (Whenever this creature is dealt
damage put a +1/+1 counter on it.)
Whenever this creature becomes blocked by one
or more creatures put X +1/+1 counters on it,
where X is the number of creatures blocking it.
They are rage, brutal without mercy, but you...
you will be worse. Rip and tear, until it is done.