Oracle Turret

The Prometheus Turret, Promethean Turret or simply the redeemed turret is a malfunctioning Aperture Science Sentry Turret that must be saved from its 'redemption' (incineration) line in order to gain the achievement 'No Hard Feelings'. When saved from redemption, the Promethean Turret spouts a variety of cryptic phrases, some referencing Cave Johnson's 'Don't Make Lemonade' speech and mentioning Johnson's secretary and assistant, Caroline. Once saved, the Promethean turret cannot in fact accompany you since you must travel through an Aperture Science Material Emancipation Grid before continuing.

The Prometheus Turret's eponymous phrase, the one that details the legend of the Greek god Prometheus, seems to reference several features about both GLaDOS and Aperture Science itself. It is also possible that the Promethean turret holds some part of Cave Johnson's personality as evidenced by its quoting Johnson's speeches. However, this is speculation.

Quotes

 * "Her name is Caroline. Remember that."
 * "Don't make lemonade!"
 * "Get mad!"
 * "Prometheus was punished by the gods for giving the gift of knowledge to man. He was banished to the bowels of the Earth and pecked by birds."
 * "That's all I have to say."