The Sentry is Your Friend! Armed with unlimited ammunition and deadly accuracy, Sentry Turrets serve as one of the main testing obstacles in the popular video game series, Portal, a mind-bending adventure that challenges you to use wits over weaponry in a funhouse of diabolical science. An automated security system previously only available to secret government facilities, the Sentry Turret Collectible Figures feature 10 unique, decorative designs to provide discreet protection in a variety of environments.