If you're having trouble you probably aren't kiting effectively. Try holding the shift key whenever you attack so if you misclick you don't walk towards the mobs. Then right after the attack animation move a step or two away from the mobs and repeat. I've just been spamming the signature move and use arcane orb when 2 or more mobs are close together and haven't had any trouble. Also use frost nova whenever you're near a crowd obv.
Just beat SK but have to go to work