Frenzied Scavengers

Frenzied Scavengers enters the battlefield with X +1/+1 counters on it
Purge- Whenever you sacrifice a creature, put +1/+1 counters on Frenzied Scavengers equal to sacrificed creatures toughness. Activate this ability only once per turn.
When the scavengers heard about the Simic Contingency Plan, they collected the freshest corpses to protect themselves from destruction