A decoy is usually a person, device, or event meant as a distraction, to conceal what an individual or a group might be looking for. Decoys have been used for centuries most notably in game hunting, but also in wartime and in the committing or resolving of crimes. When pertaining to military deception, dummies and decoys are fake military equipment that are intended to deceive the enemy.An example of a military decoy during World War I is the use of a dummy head to find and locate an enemy sniper. The papier-mâché figures were painted to resemble soldiers, with some being equipped with rubber surgical tubing so the dummy could "smoke" a cigarette and thus appear realistic, to draw sniper fire. Bullet holes in the dummy from enemy sniper bullets could then be used for triangulation purposes to determine the sniper's position, who could then be bombarded by artillery fire.
— In-game description
The Sniper Decoy is a gadget featured in Battlefield 1 for the Scout kit. The player can place up to three decoys which are essentially fake heads on top of stakes. In order to be more believable, decoys give off a Scope Glint when looked at by enemy players, and wear the faction's scout headgear. Scouts may also adjust their height while placing in order to better hide their stakes; this is done by switching stances (standing, crouch, prone). Decoy locations are marked on the minimap for all teammates.
If enemy players do fall for the decoy and manage to hit it with gunfire, it will cause them to be outlined to reveal their location to the entire team, similar to the effect of the Trench Periscope. The decoy will be destroyed in the process.