Aperture Science Sentry Turret

"Are you still there?"

- Aperture Science Sentry Gun

The Aperture Science Sentry Gun is a fully autonomous weapon created by Aperture Science featured in Portal. Sentry Guns are used within Aperture Laboratories in a manner similar to the Combine Sentry Gun seen in Half-Life 2.

Overview
The Aperture Science Sentry Gun has a single red eye, sleek appearance and predominately white color scheme common to most Aperture Science technology. Sentry Guns have only been seen in the Aperture Science Enrichment Center acting as guards in Test Chambers and  maintenance areas. Sentry Guns often speak in a child-like, artificial voice similar to GLaDOS and toilets within Aperture Laboratories. Sentry Guns have a wide variety of vocalizations that they use to communicate with. They also politely forgive Chell for deactivating them saying "I don't hate you" or "I don't blame you".

Tactics
Sentry Guns, when idle, conceal their weapons under the two plates on either side of their body. When a gun spots a target it takes a moment to deploy its weapons to fire. Sentry Gun's weapons are very powerful, able to kill Chell after only a short period of continuous fire.

However, Sentry Guns can be easily spotted by the visible laser beam emitted from their eye at all times, making it easier to avoid them. When knocked over Sentry Guns fire frantically in all directions before permanently deactivating. Like all other objects within Aperture Laboratories the Sentry Gun will disintegrate if it passes through an Emancipation Grid.

List of appearances

 * Portal
 * ApertureScience.com