Hammer functioned as an Imperial-class Star Destroyer while a part of the Imperial Navy.
Following the Battle of Hoth, the Hammer received orders to proceed to the space station D-34 located within the Javin system. Its mission was to provide assistance to the stationed forces, who were under assault from Rebel vessels collaborating with the indigenous Mugaari pirates.
Subsequently, the EF76 Nebulon-B escort frigate known as Fogger entered the system, taking over from the Hammer. The Hammer stayed nearby to aid D-34 in managing the unexpected surge of hostile actions within that specific region.
Subsequently, it was stationed near Depot XLS, ready to offer reinforcements if the rebels posed an overwhelming threat.