The Guardian of Norma is a huge battle station that also doubled as a shipyard. It was commissioned by Promethean commanders of the Forerunner Warrior-Servant rate guarding the regions around the Norma Arm, viewed as an early stage of the Shield World plan the Ur-Didact and his rate created to defend the Ecumene against the returning Flood. The station would be abandoned during the war with the Flood and left for thousands of years as a monument of the Forerunners military might. It would later be discovered through an old Luminary by the Ember Coalition, closely followed by the UNSC, the Sangheili Alliance, and the Crimson Circle.