Photographer Saeko Shirasu took a picture of a flag in the war-torn Asian nation of Uddiyana, which rouses a call for a cease fire. When the flag, Uddiyana's symbol of peace, is stolen by an unknown guerrilla sect, Saeko is assigned to document the mission of the Special Development Command unit, which is dispatched to recover the flag.

With the Metazone temple operation ending in failure and the flag still eluding them, the SDAC unit comes under heavy scrutiny from U.N. Command. As investigations begin, the frontline base is attacked by a mysterious new bipedal machine, the XR-2 Longku. Defense operations fall to Lt. Ichiyanagi, using his newly delivered HAVWC equipped with an experimental neurologically-linked control system. Meanwhile, within Uddiyana's capital city of Subasci,...