The third installment of the Metal Slug 3 series follows General Morden's plan to establish a new world order as he blasts his way through side-scrolling levels with unique themes, filled with countless enemies and bosses. The player must guide one of four heroes - Marco, Tarma, Eri, or Fio - to free hostages and ride various vehicles such as camels, elephants, tanks, and robots.
The gameplay is fast-paced and action-packed, requiring quick reflexes and strategic thinking to overcome the hordes of enemies and bosses. The player can choose from four playable characters, each with their own strengths and weaknesses, and unlock additional game modes by completing specific stages or achieving high scores.