The Mediator represented a Mon Calamari Mediator-class battle cruiser serving within the ranks of the New Republic Defense Fleet. Its assignment took place either right before or during the year 25 ABY.
As the first of the Mediator-class battle cruisers to be put into service, the Mediator was dispatched in 25 ABY under the leadership of Commander Ackdool. Its mission was to supervise the New Republic's efforts to mediate the conflict between Rhommamool and Osarian.
Nom Anor inflicted damage upon the Mediator after Ackdool granted him refuge under the guise of a diplomatic conference. The Yuuzhan Vong agent utilized a hidden A-wing to flee from the two-stage liquid-fueled rocket that was transporting him to the battle cruiser. Subsequently, as his spacecraft entered the Mediator's lower docking bay, Nom Anor triggered the remote detonation of nuclear fission devices concealed within it. This explosion completely annihilated the docking bay area, creating a massive breach in the ship's lower levels. Despite the extensive damage, the ship was not completely destroyed, and it successfully regained control of its rotation, a demonstration of Mon Calamari's superior engineering capabilities.