Willow Geist 
Creature — Treefolk Spirit
Trample Whenever one or more cards leave your graveyard, put a +1/+1 counter on this creature. When this creature dies, you gain life equal to its power.
Legality
standardNOT LEGALpioneerLEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL