Oracle Turret

The Prometheus Turret, Promethean Turret, Different 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, in a similar vein to the All-Knowing Vortigaunt. Some of these phrases reference Cave Johnson's 'Don't Make Lemonade' speech and mention Johnson's secretary and assistant, Caroline. Once saved, the Promethean turret cannot accompany the player since the player must pass through an Aperture Science Material Emancipation Grid before continuing.

The Prometheus Turret's eponymous phrase, the one that details the legend of the Greek titan 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
In the order said, once held:
 * "Get mad!"
 * "Don't make lemonade!"
 * "Prometheus was punished by the gods for giving the gift of knowledge to man. He was cast to the bowels of the Earth and pecked by birds."
 * "It won't be enough."
 * "The answer lies beneath us."
 * "Her name is Caroline. Remember that."
 * "That's all I can say."

It remains silent after this. However, whenever picked up, it will say:
 * "Thank you."

Trivia

 * It is seen in the "Aperture Investment Opportunity #3 - Turrets" video, in which it is described as "desert" colour and says "I'm different"
 * It is first seen when touring the facility with a disengaged Wheatley, right before entering GLaDOS's chamber for the first time. It is stuck in a tube, saying "Hello?" and "I'm different...", while Wheatley tells you not to make eye contact or respond, and telling it that you're not stopping.
 * It says "I'm different..." again when seen lying on a turret redemption line.
 * It speaks in a higher and slightly more off-tune and breaking voice than regular turrets.
 * Its laser sight blinks. If you spin fast enough while holding it, it won't sync up and float a bit to the side of it.
 * One of the structures at the beginning of The Fall is labeled "Tartaros 09", referring to Tartarus, also in Greek mythology.
 * The names of the turret's sound files begin with "different turret".
 * The statement about Prometheus may in fact be a reference to GLaDOS, in that she falls into the bowels of Aperture Science, and is later pecked by a bird.
 * A Commentary Node in one of Wheatley's test chambers states that the developers wanted the bird to continuously return and peck pieces off GLaDOS, also subsequently reducing her processing ability. The only reason they did not go forth with the idea was "technical reasons."