Mages are one of two support dps classes (the other being Warlock). Their main job is to not only provide good dps, but also constantly apply crowd control and silences on the opponents. Mages have Sheep (a great CC) which turns the opponent into a sheep therefore preventing them from doing anything and they also have counter spell, which either silences all trees for 4 seconds or if a person is counter spelled during a cast, they cannot cast a spell in that tree (fire/holy/shadow/frost) for 8 seconds. Alongside this, Mages have great dps, which makes them a great support class. Click the link below to learn more.