Apparently the ruler of the 4th circle of Hell. The Lord of the Fourth is a slug-like assemblage of skins that he has stitched together from souls he has tortured in the past.

He claimed that because the Fourth level is basically a void, souls have begged to have some physicality returned to them so as to be reassured that they still exist - hence the reason for skinning them. He obviously takes pleasure in the torment of his victims, and is quite proud of his other duty - the growth of the neural parasites that the hellspawn wear.

When Spawn returned to Hell for the first time since his death, the Lord of the Fourth forced Spawn to relive his past sins, skinned him, then (perhaps symbolically) removed his heart.

Lucian and his wife Daciana are the rulers of the race known as Vrykolakas. They are the ancestors of the first vampires, but have remained more consistently in the shadows than their more well known cousins.

When Mammon came to them with a young creature he claimed would be their messiah, Lucian and Daciana raised it as their own and planned for their new age. They named the child Morana, after death itself, because of its insatiable hunger for blood and pain. She was not Vrykolakas, nor was she humor or vampire. She was something unknown to the world.

Lucifer was believed to be the Angel of the Morning Star, cast out of Heaven by God only to become Satan and fight with God for all time over the souls of man.

During the events of the Apocalypse, Satan's true identity was revealed. Who Lucifer was has become unclear.

After Spawn fought Satan, Satan referred to Lucifer conquering Heaven, but he was possibly speaking about himself in the 3rd person.