Gun Metal is an action game where you control a "Havoc Suit", a combat vehicle that can change between Mech and Jet Fighter forms. You have access to a lot of weapons, including guns, bombs, and missiles. Your goal is to stop the enemy from entering your land and complete various missions.
The gameplay involves switching between different modes of the Havoc Suit, such as Mech and Jet Fighter. Each mode has its own strengths and weaknesses, so you'll need to use them strategically to overcome challenges. You'll have to defend bases, escort convoys, attack enemy bases, and fight alongside the main army.