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Valkyrie was a veteran Colonial battlestar of an unnamed class, built around the start of the First Cylon War. It played a crucial role in eliminating the Cylon's edge, and turning the favor of the war to the Colonials. The ship was still in service nearly 40 years later, serving on the Colonial front lines with its sister ships, where it was stationed over Caprica. Valkyrie is later destroyed by Cylon forces in an act of subterfuge during the Fall of Caprica. Prior to its destruction, Valkyrie was attached to the 41st Battlestar Group (TRS: "The Plan").
First Cylon War
Approximately ten years into the first Cylon War, Valkyrie was involved in a battle with Cylons near Canceron Prime, in which the ship took major damage, and was presumed destroyed. In truth, Colonial Admiralty saw an opportunity to trick the Cylons, and the ship had become part of a secret Colonial "ghost fleet" hiding in Cylon-held space, where several pilots and their planes were on detachment to the battlestar Osiris. Valkyrie's crew at the time were made to witness their own death certificates.
After the Cylons were fed more false information, Valkyrie, along with the rest of the "Ghost Fleet," participated in the successful Ghost Fleet Offensive campaign against Cylon forces, striking every Cylon base in five sectors (Blood and Chrome).
Approximately six years before the Cylon attack, Valkyrie had been ordered by Admiral Peter Corman to deploy a stealth recon ship over the Armistice Line to test Cylon resolve and gather intelligence on Cylon activities. During the mission, an unidentified DRADIS contact (presumed to have been a spacecraft) entered the area of the stealth ship piloted by Lieutenant Daniel Novacek and damaged the Stealthstar's engines before jumping away.
Two further (presumed Cylon) contacts were detected on an intercept course with the stealth ship. Rather than attempt a rescue of the disabled craft, Commander Adama ordered the stealth ship to be destroyed to prevent its discovery and capture.
In the days and years following the incident at the Armistice Line, and in particular after the Cylon attack on the Colonies, Adama came to believe that his actions had provoked the Cylon assault, having proven to them that humanity was aggressive and not to be trusted (TRS: "Hero").
Return of the Cylons
During the initial Cylon assault on the Twelve Colonies, Valkyrie, alongside battlestar Yashuman, moves in to engage the Cylons over Caprica. Both battlestars move to weapons-free status, only to be disabled by the CNP's backdoors before any shots could be fired. Valkyrie, Yashuman, a third battlestar of the same class, and their deployed Viper squadrons are destroyed shortly after (TRS: "The Plan") .