Metal Warriors takes place in the year 2102, where the United Earth Government is under siege from the Dark Axis military force led by the dictator Venkar Amon, who has waged a war against them for three years on Earth, however the titular freedom-fighting group equipped with robotic combat suits are the few remaining people defending the planet. Assuming the role of lieutenant Stone,[4] players control him through a variety of missions that initially are set in space and completing objectives such as rescuing agent Marissa from Axis 5 and capturing both an enemy supply ship and a heavily guarded asteroid base in order to obtain vital resources for the group, with the latter proving to be successful enough to promote Stone from lieutenant to captain of his crew.[11] However their recent success quickly attracts the attention of the Axis army, who engage in attacking the group's main ship with threatening enemy fire that Stone and his crew must defend with the stolen Prometheus units.[11] After the recent event, the group is tasked with disabling an anti-spacecraft cannon located in Alaska to ensure safe landing for air operations that would eventually lead to the removal of Axis forces on Earth. After stealing the experimental flying Drache machine from a jungle facility on Chile, fighting through the bombed-out Dorado city, capturing subterranean mining Axis installations and obtaining a command key from an enemy communication tower, the group finally reaches the Axis command center where a super weapon is rumored to be in construction, with Stone and his crew leading the final assault.[11][12][13][14] Once Stone reaches the depths of the center, he confronts Venkar Amon and defeats his super weapon in a battle between fully mobile flying armored suits, however Amon tries to escape with a hijacked Nitro suit but he dies incinerated alongside the base. Stone safely escapes from the explosion but his Nitro suit is wrecked after landing on the ground, marking an end for both Dark Axis and the war.