A12 Enforcer Sentry Gun

The A12 Enforcer Sentry Gun is a deployable weapon featured in Battlefield 2142. It is an autonomous machine gun fitted with an infantry tracking system. Any enemy infantry, light vehicles, or sentry guns within its 90° sight cone will be targeted.

Operation
The sentry gun performs best when set up to attack an unsuspecting enemy. While the enemy engages a more enticing target, a well-hidden gun can provide enough flanking fire to kill unsuspecting victims before they can react and respond.

Though capable against infantry, it does not have the firepower or durability to completely defend an area by itself. Rather, it should be used to supplement defenders or other sentry guns.

Combating a sentry gun
The sentry gun cannot detect targets outside of its sight cone, so it can easily be flanked. Sentry guns can still be attacked head-on with sufficiently accurate weapons.

Only bullet weapons do considerable damage. Sniper rifles can wreck a sentry gun in one shot. Grenades and explosive weapons have little effect. Sentry guns are easily roadkilled by moving vehicles.

EMP weapons can temporarily disable the sentry gun, preventing it from firing or moving.

Sentry guns in Titan mode
Aboard Titans, sentry guns have an annoying habit of detecting through walls. The sentry gun will fire on any tracked target, though the fire will not penetrate through the walls.

Defenders can use this as early warning against intruders.

A well-coordinated assault force can distract any SGs with one member who baits the gun and waits in safety behind a wall, while the rest of the team easily flanks the distracted guns and any defenders.