Nova Mage

Nova Mage enters the battlefield with a +1/+1
counter on it.
Whenever an opponent casts a spell, if Nova
Mage has a counter on it, draw a card, then you
may put a storm counter on target permanent
you don't control.
Remove a storm counter from a permanent: Regenerate Nova Mage.
If your opponents control three or more
permanents with storm counters on them, spells
you cast gain storm.