Sevarog

The Left side of the First One, Ruler of Existence. Once the most powerful being in the Existence a being of pure evil. There ruler ship was however quite tame compared to most other evil beings, they themselves rarely interacted with the realms. They spread there evil through others. Sevarog wields a great mace embedded with powerful magic, however it never reaches its true potential unless it's in the hands of its master. Furthermore to wield it one must kill several kinds of creatures. Parent of Baal, Mephisto, and Zeus. His last son Zeus was replaced by Diablo after Zeus poisoned Hades with a Shard of the First One.

When Sevarog did travel to the realms, his main goal was to spread fear. Each time the realms inhabitants fled from him or begged for there lives. One dared to stand up against him, Serath the Archangel of bravery. He cursed/blessed her with his mark inevitably causing her to be the one to dethrone him.

After the Last War of the Gods, Serath hunted Sevarog. Shattering him into Shards of the First One like the right half however she turned his soul into a mortal man. A old human mortal barely capable of moving his own Great mace, sent to die incapable of ruling anything.

"He was menacing." - Anthrax