Elemental mastery is still pretty limited in comparison to specialization in three schools of magic, though I'm not entirely sure your definition of specialization gives one the whole picture, as he evidently had some skill in the schools he was not specialized in, in the fight I watched. Regardless, if you could point out all these elemental masters you can see I'll happily see how they scale to Corban, methinks not so well.

Come now Divinity, if you can't see the difference between Corban and a 'tank who can take a punch' there's a serious issue here. However, even if there's an abundance of these powered individuals you're talking about, I doubt many masquerade as a T6/T7 and suggest they're not all that powerful. The ones that do I've already accounted for. 

Like I said, Corban is not the most overpowered character I've seen (for the tier he seems to sit at) but he's none-the-less one of the most. I'm not judging him based off his overall damage potential, there are obviously higher tiered characters than him in RPG, it's just the level he seems to be entered in comparison to his abilities that are problematic. 

And just so you know I'm objective about it, I would say my own character Fury is a close fourth place for most overpowered compared to his tier-level. His main weakness is his endurance, a weakness that few people know how to exploit (or have indeed tried.) so for all intents and purposes he is near unstoppable. Though he would still fare hilariously badly against a character as flexible as Corban.