Wrathion, The Black Prince

Flying


Whenever you cast a spell, put a +1/+1 counter on
Wrathion, The Black Prince for each of that spell's
colors.

Remove five +1/+1 counters from Wrathion:
Add {w}{w}{u}{u}{b}{b}{r}{r}{g}{g} to your mana pool.
Activate this ability only once each turn.