Captain Sessik Slessh rose to fame as the commander of the Darkshadows, an elite fighter squadron group during the Gorn/Klingon War. His political opponents accused him of abusing his father's influence and name, however his tactical abilities proved him to be his own man. While his father was a Supreme Justice and Lord of the Black Crest, Sessik Slessh became a Commander in the Republican Space Armada. He recieved his first Starship Command on the GRS Dark Dominion, which was destroyed on its first mission. It was considered a success, however, as before it was destroyed, the Dark Dominion destroyed seven Klingon Cruisers.

The GRS Oblivion was the largest ship in the fleet when Slessh took command. He became underlord of the Black Crest at a young age, and became highly influential in Gorn politics, and an icon for the conservative beliefs.

A devout Monarchist, when his ship was accidentily blasted to the Star Wars Galaxy when one of his father's weapons tests went haywire, Slessh saw an opportunity to defeat his old opponent, Captain Glagh Pshad, and install a King. Slessh failed, however, and died in the ensuing civil war.