The Emperor's Children was one of the 20 original legions of the Adeptus Astartes forces of the Imperium of Man and Bile served as its lieutenant commander. Even as a leader of men, he was rarely away from his surgeries for long. Bile saw his fellow warriors not as comrades or brothers, but as fresh test specimens ready to be experimented upon. Each was but a stepping stone in his great work; a tapestry of genetic information to be unpicked and woven anew in Bile's quest to understand the forbidden sciences of the Emperor himself. Bile did not follow the path of his fellow Battle-Brothers in their worship of Slaanesh when the Emperor's Children fell into Chaos. Instead he distanced himself from his Legion and devoted himself to researching forbidden genetic engineering technology that would unlock the secrets behind the Emperor's creation of the Astartes. His obsession with the secrets of genetic engineering has led him to commit countless crimes against nature, such as his "New Men," raving psychopaths who are even stronger than normal Astartes. Fabius has not pledged himself to any Traitor Legion in particular, and brokers alliances with each in turn, creating new warriors for his patrons in exchange for their protection and resources for his twisted experiments.
Fabius' most distinguished trait is his coat made out of flayed skin of his victims.
Bile is the most triumphant example of a mad scientist within the Warhammer 40K franchise, and is regarded as one of its greatest villains, being featured as main antagonist of several books. He appears in "Bloodquest" during a flashback sequence where he is shown capturing and torturing Brother Cloten, pushing the latter into his Red Thirst.
Powers & Abilities
As an Space Marine, Fabius has superhuman strength, speed, endurance and large, sturdier physical frame and dons a power armor that contains multiple devices of his own invention intended to fill his veins with powerful stimulants and pain killers that make him more effective in combat and which transform all the pain he feels into a form of pleasure in the best tradition of Slaanesh. Ever since he fell into Chaos, he became immortal though his body was now twisted and mutated, requiring to feel sensations all the time due to his Slaaneshi corruption.
Fabius is a genius scientist, capable of cloning and providing augmentations to others. His potential to heal is hampered by his absolute sadism, as many of these experiments tend to be absolutely excruciating and often fatal.
He had often used clones of himself to act as proxies to confront his enemies, while he is somewhere else safe from danger. He has been believed to be killed countless times, yet evaded death over and over due to duplicates dying in his stead. This technique is similar to Doctor Doom's use of Doombots.