Metal Slug puts you in the shoes of 4 experienced soldiers: Marco, Tarma, Fio and Eri. And you'll face huge waves of enemy soldiers and vehicles that you'll have to defeat to reach the end of each mission. To start playing press "Enter" and choose whether you want to play alone or with a partner. Once the mission has started, use the arrow keys on your keyboard to move your character and direct his shots and jumps. To jump, press the "X" key, to shoot use the "S" key and to throw grenades, use the "Z" key.