Congregation Gryff (200) [Outlaws of Thunder Junction]

Flying, lifelink Whenever this creature attacks while saddled, it gets +X/+X until end of turn, where X is the number of Mounts you control. Saddle 3 (Tap any number of other creatures you control with total power 3 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)