In June 2044, the Robotech Expeditionary Force (REF) fleet gathers at Moon Base ALUCE for its final attempt to drive the alien Invid from the Earth. This time, the REF has important technological advantages thanks to the help of the Sentinel races; the Karbarrans provided the industrial resources to construct this armada, while a secretive and highly advanced cybernetic race known as the Haydonites have provided advanced technology including Shadow devices, which make REF ships invisible to Invid sensors, and Syncro-Cannons, which are significantly more powerful than the REF's earlier weapons. The REF fleet is led by newly completed SDF-4 Izumo, a Super Dimensional Fortress over 1.3 km (0.8 miles) long under the command of General Gunther Reinhardt. In June 2044, the Robotech Expeditionary Force (REF) fleet gathers at Moon Base ALUCE for its final attempt to drive the alien Invid from the Earth. This time, the REF has important technological advantages thanks to the help of the Sentinel races; the Karbarrans provided the industrial resources to construct this armada, while a secretive and highly advanced cybernetic race known as the Haydonites have provided advanced technology including Shadow devices, which make REF ships invisible to Invid sensors, and Syncro-Cannons, which are significantly more powerful than the REF's earlier weapons. The REF fleet is led by newly completed SDF-4 Izumo, a Super Dimensional Fortress over 1.3 km (0.8 miles) long under the command of General Gunther Reinhardt.