Erebus

Doom Classic
Mount Erebus is a location in Hell that the Doom Marine fought through.

In Greek mythology, Erebus or Erebos is the mysterious darkness through which the souls of the dead pass on their way to Hades. Personified, Erebus was the son of Chaos and brother of the night-god Nyx. There is a real-life Mount Erebus, a volcano located in Antarctica discovered by British polar explorer Sir James Clark Ross in 1841, who named it after one of his two ships.

In Doom lore, Hell's Mount Erebus resembles a faceted jewel, the mountain almost seems to glitter with irregular prisms of bouncing light. The entire mountain floats on a lake of pernicious red ooze. Explorers can find access to Hell's Warrens from this mountain.

Doom 3
Erebus is a location in Site 1 named after "Erebus". It includes Erebus Station, Erebus Dig Site, Erebus Labs, Erebus Control, and several other ressearch and escavation sites.

Doom (2016)
Site 1 dig sites and escavations were the location where Night Sentinel statues were recovered.

The Art of Doom Eternal
In the book The Art of Doom Eternal backstory is given to an Archdemon called Erebus, also known as the Keeper of the Spire City of Dis or Slavemaster of the Dammed. He is said to serve the Dark Lord and answer to no other master, and to have ruled over a prior city called Babel. The most despicable and vile of all the Archdemons, he is said to rule over the cursed souls of Hell who are damned to labor for all eternity.

He does not appear in Doom Eternal itself, and appears to be presented as either additional lore, or be part of a plot revision that was abandoned during development.