The Dyarchy Fleet was a fleet of battleships that served the Dyarchy, a Sith principality that ruled the planet Byllura during the Republic Dark Age. Construction of the fleet commenced in about 1037 BBY, under the orders of the Dyarchy's Krevaaki regent, Saaj Calician, and the vessels were built in secret beneath the reflecting pools of Byllura's capital city, Hestobyll. By 1032 BBY, 14 vessels in the fleet were battle-ready, and the ships were placed under the command of several Force-sensitive Celegians, who could receive telepathic commands from Calician, granting the Krevaaki full control over the vessels. After Lord Daiman, the leader of the rival Daimanate state, committed the bulk of his military to the invasion of the holdings of the Quermian Sith Lord Ayanos Bactra, Calician ordered to Dyarchy Fleet to mobilize and planned to have it conquer the undefended, outlying Daimanite worlds. However, the Jedi Knight Kerra Holt caused the shutdown of the telepathic communications network through which Calician controlled Byllura, which led a series of manufacturing accidents that destroyed the bulk of the Dyarchy Fleet. The few ships that had been able to launch were destroyed moments later, after the Dyarchy fell under attack from the forces of the Arkadianate.
- Knight Errant novel (First appearance)