Judgement 12-X7, a Hunter-Killer probot serving Byss Security, operated in 10 ABY. While inside the Hyperspace Marauder, it attempted to seize the Millennium Falcon. Following the capture of the New Republic ship, the pilots Shug Ninx and Salla Zend, smugglers in the service of the New Republic, gained command of the droid's systems. They reprogrammed it to assist in the rescue of Han Solo, Chewbacca, and Leia Organa Solo from an Imperial detention facility. The droid fired upon the section of the prison holding the captives. The escape attempt was detected by an Imperial patrol, against which Shug redirected Judgement 12-X7's offensive capabilities. This action triggered a battle between the reprogrammed probot and the prison's defensive weaponry. Shug, rapidly entering the Millennium Falcon still docked within Judgement 12-X7, configured the probot to automatically fire upon the Imperials. This allowed the New Republic operatives to flee Byss just before Judgement 12-X7 was obliterated by the prison's turbolasers.