Zanisk was a Sith Lord of the reconstituted Sith Empire, specifically a male Human, who existed during the time of the Galactic War. To evade conflict with the Eternal Empire during their Eternal Empire conquest in 3636 BBY, Zanisk and his ever-present partner, Lord Adacin, chose to conceal themselves. They remained hidden even after Empress Darth Acina ratified the Zakuul–Imperial treaty. Following Empress Vaylin's demise and the creation of the Eternal Alliance in 3630 BBY, Zanisk and Adacin resurfaced, taking leadership of an Imperial offshoot group. They established their headquarters within the old Separatist stronghold located on Ord Mantell and initiated assaults on adjacent systems that had pledged allegiance to the Alliance. These actions ultimately spurred the Alliance to retaliate, resulting in the deaths of both Adacin and Zanisk as they defended their base from the ensuing attack.