These Quad 28mm fully automated machine gun turrets, commonly referred to simply as "Auto-Turrets" are placed at point of strategic interest around Apollo. As per UGC Regulation, places under heavy risk of sabotage are to be monitored by Auto-Turrets in addition to a human security force. Primarily clustered around the Armory, Fortress, Reactor, and Starport.
Operating with zero human interaction, other than routine maintenance checks and reloading, these self contained units come equipped with advanced targeting software. Capable of picking out a hostile target from an allied soldier or civilian, thanks to the standardized nano-chip implants on UGC Citizens. The Sentry Guns on Apollo can be activated at any time on any campaign by completing the Activate the Auto-Turrets side mission. Simply bring any two classes that are capable of activating turrets, (Demolition, Forward Observer, Engineer, Technician) to the Armory Hexes at any point in a Campaign.
In an effort to diversify gameplay and increase difficulty, the Sentry Guns have been removed from Survival Mode, and thus cannot be activated.