ARMA 2 is a tactical shooter focused primarily on infantry combat, but significant vehicular and aerial combat elements are present. The player is able to command AI squad members which adds a real-time strategy element to the game. This is further enhanced by the high command system, which allows the player to command multiple squads using the map.
ARMA 2 features around 80 realistically represented weapons with many variants including assault rifles, machine guns, and missile launchers, with realistically simulated ballistics. Rounds travel in parabolic trajectories and show effects of bullet drop dependent on their caliber; Muzzle velocities are modelled, and rounds lose speed and damage the longer the time and distance they travel. Sniper rifles can use stadiametric rangefinding to adjust for long-range shooting. U.S. rifles use mil-dot scopes while Russian rifles use Bullet Drop Compensation (BDC) scopes such as the PSO-1. In addition, bullets can ricochet from surfaces depending on angle of impact. Penetration is also modelled, as bullets that pass through materials suffering from altered speed and direction