Malron, Keeper of the Grove

{1}{g}{b}, {t}, Sacrifice a creature: If creature is black search your library for a creature card with converted mana cost equal to 1 plus the sacrificed creature's converted mana cost, put that card into your hand, then shuffle your library. If creature is green, add an amount of mana of any color equal to 1 plus that's creature converted mana cost into your mana pool. Activate this ability only any time you could cast a sorcery