Ackdool served as the New Republic's Commander of the Star Cruiser Mediator (a Mon Calamari type vessel) in 25 ABY; the Mediator was of the Mediator-class.
Leading up to the Yuuzhan Vong War commencing, Ackdool and his vessel, the Mediator, received orders to supervise the New Republic's attempts to mediate the Osarian-Rhommamool conflict. The radical Nom Anor devised a scheme to facilitate his escape from Rhommamool and simultaneously escalate the existing conflict. His plan involved concealing an A-wing inside a missile. This missile was then launched towards the Mediator following the initiation of a nuclear attack. The A-wing, containing both Nom Anor and Shok Tinoktin, separated from the missile after launch and subsequently departed from the severely damaged Mediator.