Dark Lord

The Nameless One, also called the Dark Lord and the Lord of the Fourth Age, is the unseen ruler of Hell. His lieutenants are the Archdemons, who enforce his will unquestioningly.

History
The Nameless One originated as Davoth, a Primeval created by the Father to watch over the realm of Jekkad. While created to be a benevolent overseer of Jekkad's denizens, he feared that one day his people would die off and leave him utterly alone and so influenced the people of Jekkad to seek immortality at all costs. The Father foresaw that Davoth's obsession would ultimately make him and Jekkad a threat to all existence, and so he sealed the realm away. Davoth became infuriated at this perceived rejection and bent all of Jekkad to his will, causing it to become a place of chaos and evil which in time came to be known as Hell. As he continued to conquer other worlds, the Father fought him and tore out his life sphere, preventing him from taking a physical form. As Davoth was once favored by the Father, the Father refused to totally destroy Davoth and instead stored his life sphere in the Ingmore's Sanctum, high above the Blood Swamps. The Father then had his own life sphere stored there alongside it. Though unable to lead his armies in person, the Nameless One continued to command them through dark whispers.

The Dark Lord first occurs in the form of a demonic voice that first contacted Olivia Pierce with the offer to ease her pain. The same voice is later heard threatening her over her failure to keep the Doom Slayer from being reawakened, and repeatedly urges the demons to oppose the Doom Slayer during various points in Doom (2016). In Doom Eternal, it is also stated that he was the one who negotiated Hell's alliance with the Maykrs.

During the events of The Ancient Gods, Part One, the Slayer retrieves the Dark Lord's life sphere and brings it to the Luminarium in Urdak in order to force him to take a physical form. It is said that should he be killed, every demon outside of Hell itself will be immediately annihilated as their connection to reality is severed. Inexplicably, his new body is a perfect copy of the Slayer's own, even bearing the Slayer's mark. The Father states that the Dark Lord is not so much a king as he is a warrior, the only being strong enough to control Hell. According to the Father, the Dark Lord is "you" (referring to the Slayer), but in the world of Hell.