In 3639 BBY, during the Galactic War between the reconstituted Sith Empire and the Galactic Republic, the Empire invaded the planet Denova for its baradium reserves. As the Empire lacked the ships to hold the planet's airspace, they landed an entire battalion on the surface, and the Republic was forced to hire the Trandoshan mercenary army known as the Warstalkers to fight back against the Empire. The battle raged for almost three months, but the six Sith Lords known as the Dread Masters used their powers to enslave the Trandoshans' leader, Kephess, and the Imperial army. The Republic and the Empire both investigated the disappearance of Kephess and the Imperial forces, and the battle ended with Kephess's defeat and death—albeit a temporary one, as the Dread Masters resurrected him as Kephess the Undying.