Vadderung says if the Old Gods trapped in Demonreach were released it would be the end and that the Bane Fire that would destroy half the continent is designed to destroyed them if they ever did.
So yeah theirs a supermax.
Yeah, and those inmates are so bad, that just dealing with their rap-sheets, does so much damage psychologically to Harry, that he may never get to all of them. Hmm, I wonder if it was that effect that corrupted Kemmler and eventually made him the evil guy he turned into.
