
The Sentinels are one of two variants of the Surgeon found within Asylum. They have been introduced in the V1.5 Beta along with the Painkillers, the Seraph Queen, the Seraphs, and the Deadworms. Like their inferior counterparts, they wear white hoods with a black void "face", but they wear black clothing instead of red, and medical harnesses. Their primary weapon is a machine gun that burst fires projectiles with deadly accuracy and range, as well as a three-pronged baton.
These brutes pose a big threat by themselves and are commonly found much later in the game, with one first appearing in the Lavaducts, a few more in the Fogometers, and the Engine Block. In The Horror, a Sentinel can be found near the first piston of the Engine Block and several more later in the Playrooms. They will hunt down and kill Shadow Man if he's not careful. It's best to either evade these monsters if they are in a group, use a Violator or two to quickly gun them down, or a charged Shadow Gun that will temporarily stun and finish them off, leaving their Lifeforce Energy behind for Shadow Man to absorb.