Zydron, Gate Lord
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Zydron, Gate Lord is a unique Vex Minotaur unit that protects the Endless Steps. It appears in the Eye of a Gate Lord story mission on Venus. Guardians have to bring its head to Queen Mara Sov of the Reef to wake its Eye in order to enter the Black Garden.
Zydron is larger than other Minotaurs, but it cannot teleport, has a weak spot below the chest and does not have a Void shield. Its body is black rather than the normal copper coloration. When Guardians first encounter Zydron, its body parts are separated. When engaging the Guardians, the separated body parts attach to each other and compose the full body of Zydron. According to the Grimoire, Zydron typically exists in a "liminal state," stretched between multiple gates or terminals, and only inhabits a body when the need arises.
Like other Gate Lords, Zydron is in charge of protecting the realms that the Vex access, and possesses a special code that links them to points in time. Zydron would then return as a Nightmare, Eris Morn compliments about how she admired the Vex Gate Lord's determination to defend their realm. 
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