Flying, firebending 2
Whenever you waterbend, earthbend, firebend, or airbend, draw a card. Then if you've done all four this turn, transform Avatar Aang.

Flying
Spells you cast cost {W}{U}{B}{R}{G} less to cast. (This can reduce generic costs.)
At the beginning of each upkeep, you may transform Aang, Master of Elements. If you do, you gain 4 life, draw four cards, put four +1/+1 counters on him, and he deals 4 damage to each opponent.