William Rolfson is the son of Autumn Rolfson and Apocalypse. During her time serving as a Horseman, William's mother had an affair with Apocalypse, leading to his birth. Fearing Apocalypse would view her son as a threat and kill him, Autumn went into hiding, raising her son by herself. At some point, William's mutant powers manifested, granting him immense powers, but trapping him in a suit designed to contain his essence.
Dark Angel Saga
William and his mother remained in hiding until they were found by Archangel after his ascension as Apocalypse's replacement. He recruited William to help him cleanse the world and recreate it in his own image. When William's mother learned of what her former teammate was doing with her son, she lashed out at him, and Archangel killed her.
Willing to take his father's place as the new Caretaker of Earth, Genocide, accompanied by his Horsemen, went to the Starcore Station to use its broadcast magnification chamber to send a message to the gods his father once served.
As the Celestial Genocide summoned appeared before him to give him the Death Seed, the Apocalypse Twins appeared and attacked them. While Uriel was killing the Celestial using Thor's enchanted axe Jarnbjorn, Eimin saved their mother and killed the other Genocide's Horsemen. Genocide was later confronted by Uriel after he finished killing the Celestial. Genocide somehow survived his encounter with Eimin and Uriel and returned to Earth.
Seeking to purge the world from the weak, Genocide convinced Warren Worthington III that Clan Akkaba could prevent him from ever becoming Apocalypse again by removing his wings. Using Warren's wings, Clan Akkaba was able to create an army of Archangel clones Genocide would use to raze the world.
Genocide was eventually confronted by Magneto and Psylocke, who had discovered his secret base at Green Ridge thanks to the Archangel on their team. However, he managed to defeat them. When Magneto and Mystique discovered his plans and tried to foil them by killing Warren, Genocide felt his Death-Flight awakening as result of Psylocke summoning Archangel, their leader, after escaping her cell. In his subsequent battle against Magneto, Genocide was killed and his Death-Flight stopped.
Bio-Furnace Energies: Genocide could generate radioactive plasma, which he often used in combat situations. At his peak, he could generate bioplasma blasts reaching a temperature equal to the core of the sun.
Armored Exo-Shell: Genocide relies upon an exoskeleton / containment suit to keep his devastating bio-energies under control. The raw energy his body produces will explode outwards if his armor is breached. The suit increases Genocide's physical strength and is highly resistant to damage or penetration. It also provides an arm-cannon for channeling his radioactive plasma into directional blasts.
- Genocide is only a bit older than fifteen.
- Genocide's mother, Autumn Rolfson, was roughly the age of the youngest New Mutants when she debuted in X-Factor #12. Even assuming Apocalypse and Famine conceived William naturally, fifteen years of Marvel time has not passed since the Fall of the Mutants. The Dark Beast and Clan Akkaba conceivably had access to age acceleration technology (Nate Grey was artificially accelerated to a teen by Sinister), but officially his age remains unexplained.
- Genocide appears to be the Earth-616 analogous of Nemesis/Holocaust from the Age of Apocalypse. However, it's unlikely they are exact counterparts. Holocaust, as Nemesis, was already a grown teenager or adult in X-Men Chronicles #1, when the original X-Men were still teens. As mentioned above, Autumn Rolfson was in the New Mutants age range, and so would have been seven years older or younger when Nemesis debuted in the AOA.
- 12 appearance(s) of William Rolfson (Earth-616)
- 1 minor appearance(s) of William Rolfson (Earth-616)
- 1 mention(s) of William Rolfson (Earth-616)
- 1 mention(s) in handbook(s) of William Rolfson (Earth-616)
- 18 image(s) of William Rolfson (Earth-616)
- 2 quotation(s) by or about William Rolfson (Earth-616)