Formerly a wizardly apprentice to Pharaoh An-Hepsu XI, Kemusar I ruled as crown regent of Osirion from -1768 AR to -1757 AR following An-Hepsu XI's disappearance. The fall of An-Hepsu XI is said to have included Kemusar's cooperation, and he is one of the few who knew the location of the Incorruptible Pharaoh's prison-tomb.1
Kemusar's true fate is unknown, although some speculate that his ghost still haunts his unfinished tomb. What is certain is that he is took the secret of his predecessor's secret tomb with him to the grave. His motivation in doing so is revealed by the message which plagued members of the royal court after his passing: "Till my betrayers and their heirs are dead, sand and soul are one. An-Hepsu XI must never be freed".1
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