During the time of the Alderaan Civil War, Nefarid, the Sith Lord, operated from a secret base situated within the Glarus Valley. Following the deactivation of the Death Mark laser's power sources by a Jedi Knight at the Mensaav Military Laboratory, Nefarid relocated the core processing unit of the superweapon's to his secret base. Ultimately, the Knight launched an attack on the installation, defeating Nefarid in a lightsaber fight, and subsequently, the Jedi annihilated the Death Mark's computer system.