America's Army

"America's Army is a round- and team-based tactical shooter with a gameplay similar to Counter-Strike, with the player depicted as a soldier in the U.S. Army.

Before being allowed to play online a player must first go through four training maps and have his or her progress saved online in a player account. Accomplishing the other thirteen training levels enables the player to become a combat life saver (CLS, medics are not depicted in game), special forces operator, SDM (squad-designated marksman, not to be confused with a sniper which is currently not present in AA), HMMWV driver, CROWS gunner, and Javelin missile operator.

The main section of the game is the multiplayer part, in which players fight either as the U.S. Army or, on "Special Forces" maps, as Indigenous forces against an opposing enemy team.

One of America's Army's unusual features is the design of the player's opponents. The players characters' are divided into two teams: usually an "Assault" group and a "Defense" one. The Assault team loses the round if the time limit runs out. Players always see themselves and their team as U.S. Soldiers or friendly Indigenous Forces. The other side is always seen as the enemy (or OPFOR in the case of training maps.)

The players on either team appear as U.S. soldiers carrying U.S. weapons such as the M16A2. Their opponents usually appear as non-uniformed people carrying Warsaw Pact weapons such as the AK-47.

The game is a medium-paced tactical shooter, similar to the Tom Clancy series of shooters. Pacing is fast in the sense that players can be killed very quickly, but the players' movements are a lot slower and the gameplay contains fewer firefights than Unreal Tournament and Counter-Strike, especially on larger maps. Unlike common first-person shooters, players are required to aim using iron sights to shoot more accurately."

http://www.americasarmy.com/