Sacrifice Gustrider Exuberant: Creatures you control with power 5 or greater gain flying until end of turn. "The elves claim the canopy. The nacatl claim the mountains. I suppose you think we ought to stay on the jungle floor?"
Illus. Wayne Reynolds
10/1/2008: The ability doesn't target, so it checks the creatures' powers only once: when the ability resolves. Once the ability resolves, it will continue to apply to the affected creatures no matter what their powers may become later in the turn.