Sentries are humanoid-esque machines lacking arms. The plating of their body is green, with their knee joints and feet being metallic grey. Their upper body consists solely of the barrel of a sniper rifle. To the right of the barrel is a small camera with pink lens, most likely the Sentry's eye. A small ammobox is attached to the Sentry's hip. Their extremely powerful legs and feet allow them to dig into the ground, making them immovable. They kill frequently, requiring blood as fuel.