Little is known about his past other than a few pieces of information. He lived in the Old West near the end of the 19th century. In a small town in Wyoming, he confronted western-hero Caleb Hammer and challenged him, wanting to best a legend. When Caleb refused to, Absalom shot him in the back, killing him. Absalom was hung for Caleb's murder, but his mutant powers surfaced at the hanging. His powers manifested and he grew spines, which cut the rope and scared the crowd away. He was shot to death, and later reawakened, revealing his immortality.
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After his mutant powers manifested, he left the town where he was hung and wondered the Earth for some time. He soon joined the Externals, other mutant immortals. In recent times, Absalom confronted and fought against Cable and X-Force. It was later revealed that he had contracted the Legacy Virus, but didn't have time to succumb to it before Selene drained his life force, after which he died.
Superstrength, eternal youth and the ability to survive most forms of death, and the ability to extrude razor sharp spines from his skin.