Joruus C’Boath was a character that only appeared during the Thrawn campaign in the Expanded Universe. He was a clone of the Jedi Master Jorus C’Boath.
Grand Admiral Thrawn tracked down the Emperor’s private storehouse on a planet named Wayland. There Thrawn had planned to use the cloning cylinders that were left behind and utilize the Guardian the Emperor had left behind. Thrawn was of the mind that the Imperials lost the Battle of Endor after the Emperor died and could no longer control the forces. Heading up to the mountain, they met Joruus C’Boath who claimed to have killed the Guardian. Thrawn enlisted his abilities on the promise of delivering Luke Skywalker and Leia Organa Solo, as well as her unborn twins into his service.
C’Boath helped Thrawn in a few battles and the Imperial forces efficiency increased. C’Boath also achieved getting Luke Skywalker to come to him. He started training Luke in the ways of the force, but Luke started to see that things weren’t right. Of the things that he taught him, many were against what the Jedi Order had stood for. Luke attempted to cure him and bring him back to the light, but he found that C’Boath’s madness was too much to overcome.
C’Boath had revealed another being that was in the galaxy that he sensed was skilled in the force, someone Luke had met named Mara Jade. Mara freed Luke and went back to the New Republic.
Thrawn was getting tired of C’Boath’s antics and had him imprisoned inside the mountain at Wayland. Mara, Luke, Han, Lando, Leia, and Chewbacca headed to Wayland to take out the cloning facility, not knowing that C’Boath was there. When Mara and Luke went into the throne room searching for a self destruct button, C’Boath greeted them with his secret weapon. He had cloned Luke from tissue from his hand that had been cut off in Cloud City.
Mara and Luke fight his clone, with Mara finishing him off. Leia, Han, and Talon Karrde entered the room and C’Boath let out a force scream, stunning everyone. He tried to bring down the ceiling, but Mara was able to use Leia’s lightsaber to cut holes in the floor so the rock could fall through. Using Leia’s mental guidance, Mara was able to charge and kill Joruus C’Boath. He exploded in a blast of dark side energy.