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Archons are part of the triumvirate leadership of a Fallen House, and serve their Prime Servitor as mechanics who delicately caretake its platings. They have an unclear symbiosis with the Primes, but are still clearly defined its servants.
If an Archon were to fall, that House's Prime Servitor becomes vulnerable to attack. Houses seem to have several esteemed mechanics called "Rising Archons" ready to assume the role should there need be. They themselves appear to be skilled mechanics, eager to prove their worth. How new Archons are selected is unclear, but during the course of the Reef Wars the House of Wolves had no less than two different Archons during the course of the war.
They are also responsible for overseeing a Fallen ritual know as the Archon's Forge, an ancient rite of passage for Fallen seeking to improve their station. Other duties of Archons are unclear, but they do seem to have a role in the ritualistic docking that Fallen Dregs are subject to. Prime Servitors also play some role in Fallen Star Flight, and it may be the Archon's role in conveying the wishes of the Kell to the Prime on the course.
In the absence of a Kell, an Archon becomes a notable figurehead by acting out the wishes of its Prime Servitor and can restore order among the House by caretaking or rebuilding the House Prime. With the demise of Skolas, Kell of Kells, Wolf Priest Keldar was able to rally the surviving Wolves by restoring Orbiks Prime.
While Riksis, Devil Archon helped Sepiks Prime rule the House of Devils after the death of their Kell over one hundred years ago. Years later, Aksis, Archon Prime was able to revive their Prime as Sepiks Perfected to control the flow of Ether and went against Fallen traditions by establishing his new authority as Archon Prime in an effort to control the Devils. Fikrul, Shadow Priest on the other hand led the Scorn after the deaths of Uldren and the Scorned Barons.
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