(The reimagined series; Caprica and Blood & Chrome)
The Basestar, or Baseship, was the primary capital ship used by the Colonial Cylons at the time of the Fall of the Twelve Colonies. They performed an analogous role to the Colonial Fleet's Battlestars, being armoured fleet carriers.
The Basestars were developed at some point after the end of the Cylon War, and replaced earlier ships of the same name. Unlike Cylon War-era Basestars or, indeed, Cylon technology in general, these Basestars were constructed with hardened organic matter, and were powered by an organic Cylon individual called a Hybrid rather than a crew.
Basestars saw considerable action during the Fall of the Twelve Colonies which, for years, the Cylon race's military was building towards. Though Basestars were not as armoured as Battlestars, the use of a CNP exploit meant that little if any Basestars were destroyed in the offensive. A fleet of Basestars continued to harass the Battlestar Galactica and a civilian refugee convoy, but much of the Cylon fleet was spread out elsewhere. In the months after the Exodus from New Caprica, the Cylon Civil War began, which led to the apparent destruction of much of the Basestar fleet, with ships under the control of the Number One; Four and Five models destroying those crewed or commandeered by the Two; Six and Eight models. Following the destruction of The Colony, it is uncertain how many Basestars survived the war, with the only known surviving vessel being crewed by Centurions, liberated from slavery by the Twos; Sixes and Eights.
The external shape of the Basestar is that of two rotating sections meeting a central structure in the middle; these sections rotate in opposite directions. The rotating systems each have three "wings", which are spread out from the centre in a Y shape. As one of the functions of a Basestar is carrying Raiders, Basestars possess large hanger bays for storage and launch, and are pressurised so humanoid Heavy Raider crews can breathe. These hangers are flesh-covered, indicative of a Basestar's organic nature.
The role and performance of the Basestars indicate that they are not nearly as well armoured or armed as Battlestars, with a Battlestar's forward cannons being particularly devestating. However, Basestars make-up for this in being able to regenerate, and are capable of storing and launching far more Raiders than a Battlestar can launch Vipers.