Bow-Harp Shaman

Channel - {r}{g}, Discard Bow-Harp Shaman: Add {r}{g} to your mana pool. You may put
a land card from your hand onto the battlefield.
Whenever a basic land is put into your graveyard from anywhere, Bow-Harp Shaman's channel cost is reduced by {r} or {g} until end of turn.