The Pharaoh of Forgotten Plagues1 was one of Osirion's earliest rulers during the Age of Destiny. He is known to have fought a war against the Jistka Imperium in an effort to expand his kingdom to the west in the 31st century before Aroden's ascension.
Needing an ally in this conflict, he built the House of Oblivion in the deserts of what is now Thuvia, to bribe the div lord Ahriman. The Pharaoh of Forgotten Plagues was eventually defeated by the Song Pharaoh in -3047 AR.2
In addition, the Pharaoh also summoned the daemonic harbinger Zelishkar to aid him in destroying his enemies, in particular the Jistka Imperium. With his service complete, the Pharaoh constructed the Labyrinth of Shiman-Sekh with the purpose of imprisoning Zelishkar.3
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