These outcasts were banished from the Sith homeworld of Korriban for interpreting the death of Sith King Adas during the invasion as a sign from the Force to reject the dark side and embrace the Unifying Force teachings of the Rakata. Fleeing Sith space aboard a commandeered Rakatan ship equipped with a Force-powered hyperdrive, these Kissai followed the Force to the hidden world of Tund in the Centrality sector, remaining in seclusion for millennia.
The descendants of these heretics were eventually joined on Tund by a number of Sith-Human half-breed colonists from the Sith Worlds in the centuries following the founding of the Sith Empire in 6900 BBY. With the Empire's fall during the Republic counterinvasion that followed the conclusion of the Great Hyperspace War, these Sith were joined by other Sith-blooded refugees fleeing the chaos in the Stygian Caldera, eventually giving rise to a unique sect of Force users known as the Sorcerers of Tund during the post-Manderon period.