Hive Thrall

Haste
Scuttle 2 (When another creature is put into a graveyard, put a +1/+1 counter on this creature.
When it has 2 or more +1/+1 counters on it, you may sacrifice it during your upkeep and return a creature
from your graveyard to the battlefield with converted
mana cost equal to 2 or lower.)