Killraven was born in the alternative Earth-691, sharing his timeline with the Guardian of the Galaxy. While his  Earth was attacke by the Martian Masters most of the superhoroes removed themselves from the struggle seen it as impossible to win. As the Masters took over the world, men not used as breeders or collaborators were trained and forced to battle gladiators-style for the Martians' amusement; women were used as breeders to supply infants, eaten by the Martians as a delicacy. This was the birth of Killraven and soon the gladiator "Keeper" saw the potential and mange to free the boy, however his brother was not so lucky and Deathraven remaind with the Masters. While traveling through the planet during th 2020 era he encounter the cyborg Skar and several experimented humans. After learning that his brother Joshua (Deathraven) was still alive and fighting Masters slaves alongside a time-traveling Spider-Man the Freeman reach the Everglades (the gang that Killraven form), where they encounter Mourning Prey. However Killraven later found that Deathraven has become a Martian collaborator. Later the plague killed most Masters and Killraven was adopted by X-23 to Earth-X and relocated by to his reality.

Alterative Realities

Earth-9930

Killraven and Blackpanter were part of this line of Avengers.

Earth-2120

The plague never killed the Masters and he still fought for the human liberation.

Earth-7305

Killraven was Captain Britain under the name  Will Of The People