The Metal Slug series, popular across the globe, is back! The battle for peace is about to begin. However, there is no guarantee of a long life of peace. As a result, the Earth Defense Organization is tasked with the task of creating the strongest defense to protect the Earth from the threats that lie ahead. A fierce war will take place. Earth is in danger. The first stage of the war is about to start! It's up to you to take part in the conflict.

Command is what matters most in the Metal Slug series. This is where you decide the fate of mankind. As a commander, you have to prepare for battle in the most effective manner possible. You need to be strong and decisive in order to lead your troops to victory! If you are not prepared, you can lose the war. But that's not all. You can also join forces with a commander from another country.