Selvala, Heart of the Wilds (571) (mythic) (Etched) | LP

This is a Lightly Played card, from the Commander Masters set. It has a color identity of: G.Whenever another creature enters, its controller may draw a card if its power is greater than each other creature's power. {G}, {T}: Add X mana in any combination of colors, where X is the greatest power among creatures you control.