played this religiously when it first came out
before you level a champ, check to see if they have sorted out class balancing yet. when I played it was basically roll a mage and you'll be best dps/healer/tank/support.
might have to update it, and give it a little play
and for those wondering what build to do, late game you have multiple. I.E I was main DPS but also had 2 tank trees and armour sets