Convoke only works when you cast convoke spells, and only to reduce the mana cost of the spell being cast
3) They have tutors to make their awesomeness reliable
In applicable matchups, this is a strictly better Mana Leak, making it easy to win counterwars or delay your opponents trying to set up some powerful play
Beyond that, however, is Ariels rarity itself: the relatively new Iconic rarity: something a step beyond the legendary Enchanted status that brings added challenge to pulling this gorgeous card
When youre playing a proactive game and trying to apply pressure, you dont have the same luxury of spending a mana here and there to improve your draws
Second, some amazing sorcery spells were mentioned to keep your hand filled