Three-Headed Greyscale

Flying, double strike, trample
Whenever Three-Headed Greyscale attacks, you
may exile a creature card from your graveyard. If
you do, put a +1/+1 counter on Three-Headed
Greyscale.
As long as Three-Headed Greyscale has three or
more +1/+1 counters, it can't be blocked except
by three or more creatures.