Resurrection Ship
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A large ship, apparently escorted by two basestars and approximately a dozen support vessels, is part of a Cylon fleet which tracked Galactica for some time after its departure from Kobol (Final Cut). The battlestar Pegasus located this ship and its escorts sometime after the Fall of the Scorpion Ship Yards and used it to locate Galactica. The two ships rendezvoused and began planning a joint strike on it, but tension between Admiral Nelena Cain and Commander William Adama quickly threatened to derail the operation (Pegasus).
Its function is presently a complete mystery. Admiral Cain speculated that it was a command and control ship. Adama suggested that it might be a Raider factory.