Adacin, a Sith Lord of the Human species, was a female character who existed during the Galactic War within the reconstituted Sith Empire.
To evade conflict with the Eternal Empire during their Eternal Empire conquest around 3636 BBY, Adacin and her ever-present ally Lord Zanisk chose to conceal themselves. They maintained this hidden existence even after Empress Darth Acina ratified the Zakuul–Imperial treaty. After Vaylin's passing and the establishment of the Eternal Alliance circa 3630 BBY, Adacin and Zanisk resurfaced, assuming leadership of a dissident Imperial group. They established their headquarters within the previous Separatist stronghold located on Ord Mantell, initiating assaults on adjacent systems that were in league with the Alliance. Ultimately, this provoked the Alliance to retaliate, resulting in the deaths of both Adacin and Zanisk while defending their stronghold from the counterattack.
Lord Adacin is a character featured in Star Wars: The Old Republic: Knights of the Eternal Throne, a massively multiplayer online roleplaying video game, specifically during the culminating boss encounter of the "Inferno" Uprising.