Pride

Pride enters the battlefield with two +1/+1
counters on him.
Devour 1, ouroboros (If this creature would be
killed, remove a +1/+1 counter instead)
When Pride attacks, if you don't control a
Shadow creature token, create a 5/5 black
Shadow creature token that's tapped and
attacking. When Pride leaves the battlefield, sacrifice all Shadow creature tokens you
control.