Noxious Hatchling

This creature enters with four -1/-1 counters on it.

Wither (This deals damage to creatures in the form of -1/-1 counters.)

Whenever you cast a black spell, remove a -1/-1 counter from this creature.

Whenever you cast a green spell, remove a -1/-1 counter from this creature.

Power/Toughness: 6/6