During the Great War, man-made communication systems were still crude and unreliable, so dogs and pigeons were used extensively to carry messages. In the War Pigeons game mode the opposing sides compete to use messenger pigeons to call in artillery barrages on the enemy. When the game starts, a pigeon coup with a messenger pigeon is placed somewhere on the map. Locate the pigeon before the enemy and carry it to a safe location out in the open. There you prepare a message and send it off, calling for artillery support. Once a message is successfully sent an artillery barrage will strike the enemy.