During the Dark Angel Saga, the Horseman of Pestilence Ichisumi became pregnant with Archangel's heirs.Some time after his defeat at the hands of X-Force, Ichisumi gave birth to the twins Uriel and Eimin. Soon afterwards Kang the Conqueror kidnapped them and disappeared The Twins reappeared in the modern era, when Genocide, son of Apocalypse, contacted a Celestial Gardener. He hoped to receive the Death Seed and replace Apocalypse as Archangel had As the Gardener judged his worth, Uriel and Eimin appeared. Using the axe Jarnbjorn, Uriel killed the Celestial. Together, he and Eimin defeated Genocide's forces. They then attacked the Peak.
During the Age of Ultron storyline, Kang the Conqueror took the Apocalypse Twins as teenagers from their time in the concentration camps to the timeline which was accidentally created by Wolverine when he killed Henry Pym to prevent the creation of Ultron. Kang the Conqueror gave the Apocalypse Twins the mission to kill Colonel America. They failed, but end up murdering Havok and his wife Rogue. Kang the Conqueror sent them back to the concentration camps.
Using a Celestial Death Seed, the Apocalypse Twins resurrect Banshee, Daken, Grim Reaper, and Sentry to be the Horsemen of Death (the Apocalypse Twins' version of the Horsemen of Apocalypse).
Powers and abilities
Like his father, Uriel has two sets of back mounted metal wings that can generate and fire razor sharp blades of energy. He can bend space and time within a certain radius, create a pocket dimension of accelerated years and release waves of artificial time to instantly kill victims. These latter powers are not related to his mutation but of unknown origin, although presumably given by Kang. Uriel wields in battle the mystic axe Jarnbjorn, Thor's old weapon. Uriel seemingly died in Uncanny Avengers #16 but was revealed to have the timeline changed to altered.
Eimin is a mutant, possessing two sets of metal wings which are able to fire globes of highly potent acid. By unknown means, her natural abilities are "intertwined" with the temporal powers of Kang, causing those afflicted by her acid to be trapped in eternal agony as it burns them alive. As a child, under orders of Ahab, her eyes are removed by her brother slashing her face with his wings as punishment for trying to escape a Red Onslaught prison camp for mutants. As a "gift" from Kang, she is given a type of time-space synesthesia that allows her to see visions of possible futures when listening to music. Despite this, she functions as well as any sighted person, even engaging in combat, flight, and aiming her poison spheres.