Korma, Roaming Keep

Whenever you cast a blue spell, tap target
creature an opponent controls, it doesn't untap
during it's controller's next untap step.
Whenever you cast a green spell put a +1/+1
counter on Korma, Roaming Keep.
If there are 6 or more counters on Korma, he
gains, {t}: Add one mana of any color for each
tapped creature your opponents control.