As a multi-target mage, Khamet is a great example of what people should want. With his basic attack dealing solid damage against 2 targets and a 400% increase when making the first hit (which resets every 7 attacks), he is able to single-handedly knock down any group of enemies in the game. When you add his attacks bouncing when they kill, and the high damage multiplier on his ultimate, he should be the first place you look if you need a mage.