Sentinels are weaponized versions of Watcher security drones. They are large, flying DeeBees that have both defensive and offensive capabilities. Sentinels have a regenerative shield that can come back up rather quickly once deactivated. They are armed with a Salvo Rocket Launcher, a heavy weapon that can be picked up by the player if it is destroyed.
Like Guardians, Sentinels have two distinct advantages on the battlefield. Their ability to fly gives them an elevated position from which to fire their damaging rocket launcher, often forcing players out of cover. Their shielding offers protection from enemy fire whilst also allowing it to fire their own weapon. However, a Sentinel can only fire four rockets per salvo, with a sizable reload time between salvos, and their shields only offer frontal protection, leaving it vulnerable to attack from the rear and sides.