Featuring ten tanks from World War II, Mobile Armor is a mission-based shooter in which you control the "Mars army tank" in battle against a succession of "Earth army tanks." Completed missions in single-player story mode become available for two-player free mode, with one player manning the cannons and the other the tank, as well as for two-player VS mode. In VS mode, five tanks are available from cleared story mode missions, with another five added based on the number of cumulative defeated Earth army tanks.