John Cavil (alternate)
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While originally a human, Cavil would later become a Humanoid Cylon, after he risked his life to help people out of a burning wreckage, during which time Kobol had fallen into chaos. Cavil, who was gravely wounded in his rescue attempts, while trying to help the survivors from the explosion of the Thirteenth Tribe's first resurrection facility, is downloaded into a new body as a reward for his heroism and selfless acts. He is assisted through the resurrection process by a fellow Cylon named Ellen, whom he reveals his name unto her.
Cavil would later join the Thirteenth Tribe as the tribe left Kobol and set out to search for a new planet to live on: Earth. Cavil often came at odds with Michael Tigh regarding many issues, and the two developed a rivalry and resentment towards one another lasting years. Cavil also begins to embrace his new Cylon physiology and culture, and begins to resent the Kobollian humans and their nature, believing the humans to be flawed and destructive, where the humans would eventually destroy themselves. He begins to embrace his new life as a machine and resents his previous life as a human, becoming anti-human. Cavil also starts up a friendship with Ellen, with an indication that he may hold romantic feelings for her; whether Ellen reciprocated Cavil's feelings for her or had any knowledge of them is unknown.
When members of the tribe are stranded on the Alage planet, with no resurrection and are cut off from the rest of the fleet, Cavil is amoungst the few of the Cylons to have survived the explosion and crash of the tribe's main resurrection ship. Cavil later discovers Ellen's body, having been killed in the explosion and crash. He is deeply affected by her death, and later privately mourns over her death and buries her body amoungst the other graves of Cylons who were killed in the crash. Although he is angered at Michael Tigh for being responsible for leading all of them down to the Alage planet, he is satisfied that they had enough alage on this planet to keep them from starving.
When a virtual being in the form of Pythia, (in reality: Aurora having taken physical form of the deceased Pythia), mysteriously appears to help the Cylon survivors by guiding them to Earth, it is likely believed that Cavil assisted Pythia and the other Cylon survivors in rebuilding a new resurrection ship, and with Pythia rewriting the survivors' genome to make biological procreation possible amoungst them. Eventually, the survivors were able to reach Earth, where they established and build their new home there.
Upon settling on Earth, he would later have a daughter named: Ellen Cavil, named after Ellen, the woman he loved and lost on the Alage planet years ago. Ellen would later marry Saul and would bear his surname. Ellen, much like Saul Tigh, would later become a member of the legendary Final Five.
Nearly 2,000 years later, Cavil would be killed by his own daughter, in an attempt to save Saul's life and prevent her father from carrying out his plans to cleanse the tribe and rebuild it in his own image, an attempt which proved to be futile.
2,000 years later, Cavil would become the grandfather to the Significant Eight. His grandson, John Cavil, would be created in his image by his daughter and members of the Final Five, with the Ones adopting certain aspects of his own personality unto themselves, hereby, continuing on his legacy.