Auromoxa, Cosmos Edge

Flying, Vigilance, Affinity for counters
Auromoxa and other creatures you control enter the battlefield with a cosmic counter.
When a creature with a cosmic counter attacks or
blocks you may remove that counter and choose one:
-Target creature phases out until your next turn.
-Put two +1/+1 counters on target creature.
-Target creature becomes a 6/6 blue dragon with
flying and loses all abilities until your next turn.