Chaeleich, Emerald Arrow

+1: Up to 2 target creatures get -1/-1 counters or one target creatures gets two -1/-1 counters.
-X: Search your graveyard for a creature card with converted mana cost equal to X. Put it onto the battlefield, shuffle your library if searched.
0: If creatures in your graveyard have a total power of 16 or more, transform Chaeleich, Emerald Arrow.