Battle of the Resurrection Hub
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After the Demetrius returns with the Cylon rebel leader Natalie, she proposes an alliance between the rebels and the Colonials. She offers the humans the chance to destroy the Cylon's central resurrection facility. In return she wants help to unbox Number Three and learn what she knows about the Final Five. In preparation, half of Galactica's air wing is transferred to the Rebel Basestar. However, before the plan can be put into action Sharon Agathon kills Natalie, believing to prevent her from taking away her daughter Hera as she saw in the dream of the Opera House. Simultaneously, Laura Roslin has the rebel Hybrid reconnected, who unexpectedly jumps the ship away (Guess What's Coming to Dinner?).
The Hybrid is determined to have panicked after sensing Natalie's death and jumped as a result. She follows the Hub with her jumps, still giving the combined force a chance to implement their plan. To prevent an early detection by the enemy, the Vipers are running with their engines and electronics cold, instead being towed by Heavy Raiders piloted by humanoid Cylons. The human pilots are initially very reluctant to fly alongside the Cylons and be so heavily dependent on them, but a Number Eight convinces them to place the same trust in her as they do in Sharon Agathon.
Once the cables are cut, the Vipers attack and a Raptor flown by Lieutenant Eammon Pike disables the Hub's FTL drive with two missiles, thus stranding it. Karl Agathon and the Eight then board the Hub in a Raptor to find Number Three, who has already been unboxed by Cavil and Boomer. They find her after she has killed Cavil and forced Boomer to run and take her to the Raptor and off the Hub. Meanwhile, the rebel basestar engages the two escort basestars, but Gaius Baltar is badly wounded when two missiles strike the ship. Once Three, Agathon and Number Eight are clear of the Hub, the Vipers launch several nuclear missiles into it, destroying it and both of its basestar escorts (The Hub).
With the Hub being vital to the functioning of all other resurrection ships and downloading facilities, the Cylons are now truly mortal, which is welcomed by the rebels, but feared by the mainstream of Cylon society. In addition, D'Anna Biers is the only Three left, since all other copies' consciousnesses were destroyed on the Hub. Resurrection is unable to be rebuilt as its a technology of the Final Five and only they know how to rebuild it. Unfortunately, the loss of resurrection made Cavil (who apparently was able to resurrect before the Hub was destroyed) send Boomer to kidnap Hera to find out how she came into being so his faction could continue through reproduction. His actions lead to the Battle of The Colony where Cavil and all of his forces finally fall to Galactica. Thanks to the destruction of the Resurrection Hub in this battle, the deaths of all of Cavil's faction are permanant. Among those who end up having permanant deaths as a result of the destruction of the Resurrection Hub are D'Anna (who eventually dies alone on Earth of unknown causes), Cavil himself, Boomer, Tory Foster and Samuel Anders.