Rotting Crocodile

Unleash (You may have this creature enter the battlefield with a +1/+1 counter on it. It can't
block as long as it has a +1/+1 counter on it.)
When Rotting Crocodile is put into your graveyard from play, put -X/-X on all creatures, with X being the number of
+1/+1 counters on Rotting Crocodile.