Trey, Ornithologist Supreme

Kicker {2}{x} (you may pay an additional {2}{x} as you cast this spell)
Flying
When Trey, Ornithologist Supreme comes into
play, if you paid the kicker cost, put {x} feather counters on it.
All birds get +1/+1 for each feather counter on
Trey, Ornithologist Supreme.