While literally the entire capital of Mibothen had become a war zone, it couldn't be any different in the center.
Zylok was a very, very strong player, perhaps one of the strongest Evolved technically speaking, due to his class skill set. Even so, Zylok's strength paled in comparison to the power of Belial, the strongest demon.
In Muspelheim, just uttering the name 'Belial' is enough to make many souls tremble. As hell is an abyss in the middle of the desolate landscape of the kingdom of the fiery giants, many of the troubled souls in this world, even though they weren't hand-picked to suffer in hell, choose to face this prison with the promise that if one day they reach Surtr's feet, he will forgive them and throw them back into the world of the living, and some have even reached the first circle of hell, escaping and slipping between the circles, but no one has ever managed to pass through Belial's circle.