Flagship of all Alliance and Atritians , commonly known as "Old Lightship" , secret project of Celeborn, Atritians Fleet Chief Commander. Ship is pinnacle of Atritian technology, it consumed most of their resources and "Phantoms" to create strategic weapon to turn the tide of most strategic battles. Ship serves as home of most noble Phantoms as well as replicas of most valuable technologies.
Ship has its "personality. Her second purpose is to perceive most valuable artefacts in case of destruction of Alliance homeworld. Third purpose is to provide massive shield to whole fleet.
Thats because it appears only fo moment in battle , destroys enemy or warps all fleet out and hide itself in safe portion of space.