First encounter: "Ah more subjects for the Master's experiments! What? You don't want to be an experiment?! But look at me - see what you could be! Ok, ok, just stay still while I finish this spell ..."
On defeat: "Oof! No more experiments I promise!"
Dr Xesc is the eighth Superboss. He appears at level 4000. When defeated for the first time, he will drop 43 Infinity Gems.