Artifact
Whenever you draw a card, put a +1/+1 counter on Ontarachie Curio.
{T}, Remove a +1/+1 counter from Ontarachie Curio: Create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”
{1}{G}: Ontarachie Curio becomes a green 2/1 Dryad creature until end of turn. (It's no longer an artifact.)