The ASU 7 Automatic Sentry Unit is a stationary sentry weapon used by the Earth Defense Force to guard important and restricted areas.
These sentries were developed by the ASU company and deployed by the Earth Defense Force to defend many places on Earth, usually cities, and to secure remote properties on extraterrestrial colonies.
In Cairo, the turrets were deployed to defend strategic points before it became overrun by Mental's forces where it still remains active. They will automatically shoot Mental's Horde, Sam or anyone else due to their system not being able to distinguish between foes and friendlies. They are armed with an XM-214-A Minigun which is deadly due to its high rate of fire and firepower. They will search for anything that moves with their laser sight. They cannot be destroyed by any weapons and can only be deactivated by a switch that activated them.
They are only encountered in the city of Cairo during No Place to Hide where Sam encounters them still activated and defending the deserted part of the city area while getting pass them to reach Garret's crash site. Later, Sam encounters one during The Dark Bride, which is still defending the temple area, and the minigun on it can be picked up to be used. Several turrets are also seen in Together Forever, where they guard the entrance to an abandoned military base.
"Originally developed to cheaply secure remote properties on extraterrestrial colonies, ASU's became very popular companions for EDF forces battling against Mental's hordes. XM214-A Minigun is the most popular primary weapon for any ASU's, its firepower can stop large waves of smaller enemies without any assistance from the operator. A heavy-duty servo mechanism enables the ASU to quickly refocus between two targets in a fraction of a second. An infrared laser scanner can detect moving targets over an adjustable area of operation. Unfortunately, the simple and robust aiming system is not capable of discerning foes from friendlies, so it shoots at anything that moves."
- Since they cannot be destroyed by any weapons, the only way to shut them down is by switching the lever off that connects to them to deactivate them.
- Observe the sentries laser movement and their position before making a move.
- You can also reactivate them back for the use to fend of large wave of enemies or for defending yourself.
- You can also use the sentries to save up your ammunition.
- The turret you encounter during The Dark Bride will shoot at Mental's Horde. Do not pick it up until it has finished its assault, otherwise you will waste ammunition and you have to fend off Mental's Horde by yourself.
- It takes 3 seconds to kill the player regardless of their health, and it takes 12 to 15 seconds to kill a Major Bio-mechanoid.
- It is unknown how the minigun never runs out of ammo after being activated for a long period of time, though it is possible that the turret uses a techno-magical ammunition replenisher (TMAR).