Woodlurker Mimic

Woodlurker Mimic

Creature - Shapeshifter | Power/Toughness: 2 / 1 (CMC 2)
Whenever you cast a spell that's both black and green, Woodlurker Mimic has base power and toughness 4/5 until end of turn and gains wither until end of turn. (It deals damage to creatures in the form of -1/-1 counters.)