Army Defender is an action shooter in which players must defend their base against enemy attacks by controlling a machine gun tower designed to eradicate enemy waves. Attackers include soldiers, tanks, paratroopers, helicopters, jet fighters, bombers and elite commandos. The enemy type influences the color of ammunition. Power-ups are available when a super bomber delivers them onto the base. After retrieving a power-up, players are able to upgrade their tower for a limited amount of time. Upgrades include flamethrowers, rocket launchers or concussion grenades that will help contain enemy progression.