Battle of the Trinary Star System
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Following the retreat of the Raiders during the Battle of the Ionian Nebula as a result of their detection of one member of the Final Five in the Fleet, two Cylon factions propose different solutions. The Ones, Fours and Fives vote the lobotomize the Raiders in order to assure their obedience to orders, while the Twos, Sixes and Eights vote against the plan, arguing that they should attempt to learn the identities of the Final Five. When a single Eight model, Sharon Valerii, unprecedentedly breaks with her model and votes for the plan to reconfigure the Raiders, the leader of the losing faction, Natalie Faust, secretly has the telencephalic inhibitors in the Centurions removed, giving them sentience. Enraged at the modification of the Raiders, the freed Centurions side with Natalie's faction and helps purge numerous basestars of the Ones, Fours and Fives (TRS: "Six of One").
Soon, the Cylon fleet becomes separated into two segregated factions controlling their own basestars. During a meeting between the two factions, Natalie gives Cavil her conditions for reunification: the end of the Raider modifications and the unboxing of the entire Number Three line in order to discover the identities of the Final Five. After presenting the conditions to his faction, Cavil tells Natalie that the Fours and Fives have agreed to their terms. He informs them that the Number Three line is being downloaded at the Resurrection Hub and that the nearest accessible server is six jumps away. Both factions agree to remain on their own ships during the journey (TRS: "The Ties That Bind").
Upon jumping to a trinary star system near the orbit of a ringed gas giant, Natalie's ship learns that the Resurrection Ship failed to make the jump. With Natalie's three basestars grouped together, Cavil's five basestars circle around them. Realizing that they intend to attack, Natalie orders the fleet to jump, but the initial salvo disables their FTL drives. Unable to escape, the ships are hit by a constant barrage of missiles and Raider attacks, with one of Natalie's basestars quickly destroyed.
Eventually, Natalie's other basestar is destroyed, and her own basestar is heavily damaged. Furthermore, her Raider wing is almost completely destroyed. As the engagement takes place outside of resurrection range, all humanoid Cylon and Raider deaths are permanent. Believing the Rebel basestar to be either destroyed or crippled, Cavil's forces retreat from the area, leaving a large field of debris where ordinance continues to explode among the wreckage for some time.
Leaking fuel and set adrift, Natalie's ship enters orbit around the nearby gas giant. A heavily damaged Heavy Raider piloted by a single Number Two copy is sent out into deep space, where it is found by the Demetrius. The Two proposes an alliance between the Cylon rebels and the Colonials (TRS: "The Road Less Traveled"). A Raptor team, led by Kara Thrace jumps back to the basestar and uses their ship's FTLs to jump the basestar to the Demetrius and then to rendezvous with the Fleet. This alliance eventually leads to the Battle of the Resurrection Hub and the Battle of The Colony where resurrection is destroyed and Cavil and his forces finally fall to Galactica's crew, aided by some Rebel Cylons (TRS: "Faith"; "Guess What's Coming to Dinner", "The Hub", "Daybreak, Part II").