At some time either during the Great Galactic War or earlier in the Cold War, Nomen Karr operated as a Jedi spy for the Republic. For some time, he had embedded himself into the vast intelligence network established by Darth Baras, but eventually was forced to abandon his assignment. It was there that Karr betrayed Baras.
Later, during the Cold War, Nomen Karr sought to defend his apprentice when he challenged Baras to a duel at this safehouse in Nal Hutta. Baras ordered his apprentice to go in his stead, and there, Jedi Master and Sith apprentice dueled. Nomen Karr was eventually defeated and his apprentice, turned to the dark side and recruited to the Sith Order by Baras' apprentice.
- Star Wars: The Old Republic (First appearance)