Dorn-Mar Garth

Dorn-Mar Garth was a pureblooded Sith Lord who followed Darth Harkis he also tried and failed to murder Ludo Kressh. However he survived the incident and escaped to yavin 3 and began training Sith apprentice's to avenge Darth Harkis.

Eventually he was ready to attack the empire. When he arrived ruins where all that remained so he gradually built up a new empire until vitiate called him to nathema where he was killed in the nathema ritual.