During the era of the Galactic Civil War, a conflict took place above Derilyn. A group from the Alliance managed to sneak onto the Derilyn Space Defense Platform with the goal of eliminating the Star Destroyer known as the Brazen. While this operation was underway, the Khuiumin Survivors, who had been in touch with Alliance operative Shondra Del, showed up and attacked the Imperial troops, helping the Alliance team get away. The Alliance team successfully detonated explosives on the Brazen, leading to its destruction and also causing significant harm to the Derilyn Space Defense Platform.