Z-5080 Promethean vision
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Developed for use by the Prometheans, an elite class of Forerunner Warrior-Servants, Promethean vision allows the user to detect shapes and movement through solid barriers. It has been adapted for use with the MJOLNIR Powered Assault Armor (GEN2) in conjunction with Version 4.0 of the Visual Intelligence System, Reconnaissance. It can also function with John-117's uniquely upgraded Mark VI MJOLNIR suit. Its effectiveness is somewhat limited by its difficulty and inability to perceive the use of active camouflage and the Type-27 hologram, respectively, as well as the noise it produces when it is in use. The Promethean Vision's ability to see through solid surfaces has been the source of many UNSC victories during the Requiem Campaign.
The behavior of Promethean vision differs between game modes. In War Games, Promethean vision has far greater difficulty detecting enemies using active camouflage. A player utilizing active camo will not glow orange, but rather appear blue in the manner a player appears if they are utilizing the Stealth Support Upgrade. Promethean vision will also not differentiate between a player and a hologram, making it difficult to tell them apart. Interestingly, if a player utilizes both the Stealth upgrade and hologram ability, their hologram will still display bright orange while the player is blue, allowing alert players to differentiate between the two.
In campaign and Spartan Ops, however, Promethean vision has no difficulty detecting active camouflage. Targets still glow bright orange, even when using active camo. This makes Promethean vision incredibly useful for detecting Covenant units utilizing stealth technology.
Promethean Vision is the only armor ability which can be used while carrying a detached turret. Using any other armor ability will cause the player to drop the turret.
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