Hydroth was the Merraxen master during the Merraxen-Sith War. He ordered his slave-warriors to attack the Original Sith, only to be defeated by the Sith army. Even after his elite defeated the Sith, he was betrayed by Nihusar. In the end Hydroth surrendered to the Sith so that he could bring Nihusar to justice.
During his time in slavery, Hydroth freed and married a Human slave-warrior, named Setra, an act forbidden by Merraxen law. Therefore, the few remaining Merraxen assassins killed Hydroth in his sleep.