As a reward for this act of loyalty, a great ziggurat was built, a mighty structure which served both as his temple and his prison. Within this temple he built many wondrous engines of destruction and power, and taught Magi the knowledge of the stars. The most learned of the Magi monitored Agathoth day and night, distrustful of his motivations, watchful should he betray them. They became enthralled by him with time. When Abu Hassan instructed the Magi in ziggurat to reverse the ritual, thus banish Agathoth from this plane, they turned against him and the Order. These renegade Magi laid Agathoth in a tomb carefully warded against the machines employed against his kind, a place he may rest in safety.
Now he is sleeping in his Temple, which PC was asked to find by Antidas/Gaelius/Meru/Balzaar. Old "Witch" Azra cautioned PC against trying to wake up Agathoth as the consequences might be disastrous. Agathoth know this world for what it is. Humans will bow to any fool wearing a golden crown, but they hate and fear that which is different. A tribal mentality. He need one human to be the face that rules the tribes. So that he may rule from the shadows. PC may be that human.