[Source] Magnetar rifles were experimental disruptor rifles developed by the Galactic Republic during the Cold War that were specifically designed to disrupt energy shields. A supply of such rifles was kept in the armory of the secret prison on the planet Belsavis during the Galactic War between the Republic and the Sith Empire. During the Battle of Belsavis a gang of prisoners known as the Condemned broke into the armory to collect weapons and use them against the Prison Administration Center. Warden Graal then sent a Republic-aligned individual to recover the magnetar rifles, as they couldn't risk the prisoners getting hold of them.