Promethean Knight

"I have led you, my Prometheans, for thousands of years, and I shall continue to lead you. Rise! Rise, and protect the Forerunners! Rise, and protect the galaxy!"

- The Didact to his legions of newly-created Promethean Knights.

Promethean Knights are a class of mechanized Forerunner Promethean warriors. Several legions of Knights represent the central occupying force in the shield world of Requiem, alongside a number of other Promethean machines.

Overview
The Knights are bipedal, fully weaponized mechanical warriors designed to operate and eliminate threats in a wide variety of environments. While the Knights are fully machines, their AI is a result of organic minds transformed into software format via a device called the Composer. This extreme measure was intended by the Didact to create an unstoppable army, completely immune to Flood infection, near the end of the Forerunner-Flood war. The Didact's Promethean Warrior-Servants were the first Knights, but later a large number of humans were "conscripted" to expand their numbers. Eventually, even the mightiest Forerunner war machines proved unable to halt the parasite, necessitating the use of the Halo Array. In addition, the Composer was unable to fully copy the personality or "soul" of an individual, leaving the Prometheans intelligent, but bestial and ruthless.

They utilize a broad arsenal of weapons; in addition to a hard light blade weapon on one hand, they also use various Forerunner ranged weapons, such as Scattershots, Suppressors, Lightrifles, Binary Rifles, and Incineration Cannons; their dedicated armament largely depends on their class and role. They frequently employ pulse grenades in combat. They are able to deploy Watcher drones, carried in the back of their armored carapace, for combat support. The Watcher sentinel can greatly improve the Knight's combat capabilities by raising hardlight shields, reviving fallen Knights, summoning Crawlers, building automated turrets, and flinging back enemy grenades while distracting them with its own weaponry. Some subtypes also make use of autosentries, in addition to the support that they can already summon.

Knights are remarkably agile, and in addition to using their limbs for conventional movement they are also capable of translocating over moderate distances, allowing them to either swiftly retreat from the battlefield or to flank their enemies. Although not commonly seen in the field, Knights can also be deployed from warships and are equipped with thruster engines for maneuvering. This capability was used during the Forerunner-Flood war, when Knights were deployed to board and destroy Flood-controlled ships from within.

Upon taking critical damage, Knights completely disintegrate, a process that Cortana described as a "data purge." Their bodies erode away from where the fatal shot was received and dissolve into glowing particles. After disintegration, a small ball of swirling light is left behind for a brief period; a Promethean Watcher can use this remnant to recreate and revive the Knight; however, an individual Knight can only be revived in this manner once. If a Knight is destroyed, revived, and then destroyed again, the Knight's body disintegrates completely, leaving nothing behind.

Appearance
Knights have two sets of arms; two large, artificial arms at each shoulder in which the weapons are mounted and two smaller arms below the shoulders. The larger arms are composed of separate segments held in formation through an energy field. Knights also have a comparatively smaller set with small, five-fingered hands. These smaller arms are more "organic" in shape and are physically attached to the Knight's body.

Knights are covered in patterns of light and have a fire-like glow around their heads. The colour of this light indicates their allegiance. Those with blue lights are controlled or otherwise loyal to the Librarian or her remnant; upon the Didact's release from his cryptum the Knights' colour changed to orange, indicating they were now under his control. The head features an armored helmet with glowing eyes and what appear to be grimacing jaws with rows of teeth. This helmet assembly can be retracted in two sections, revealing a glowing humanoid skull underneath. Cortana initially theorizes that this is because the Prometheans have mimetic capabilities, and had based the skull on scans taken of the Master Chief; it is later revealed that the Forerunners are humanoid in appearance, and that the skull appears to be based on that of a Forerunner as opposed to a human.

Subtypes

 * Knight Lancer - a variant equipped with long-range weaponry, greater mobility and enhanced tracking capabilities.
 * Knight Battlewagon - heavily armored variant, equipped with Scattershot.
 * Knight Commander - command-and-control unit for Knight forces.

List of appearances

 * Halo 4
 * Scanned
 * Halo: Silentium