Product Details
Flying When Clockwork Avian comes into play, put four +1/+0 counters on it. At the end of any combat in which Clockwork Avian is assigned to attack or block, remove a counter. X, T: Put X +1/+0 counters on Clockwork Avian. You may have no more than four of these counters on Clockwork Avian. Use this ability only during your upkeep.
Rarity: R