|This article is about the old man living in Aten. You may be looking for the Egyptian soldier.|
Around 38 BCE, Khui was punished for not conforming to the sole god Aten, who was worshipped by pharaoh Akhenaten. For this, he was held in a cage in the Chambers of Reflection. Later, he was found by the Hidden One Bayek of Siwa, who had came to Aten through a portal connected to Akhenaten's tomb in the living world.
Bayek freed Khui and carried him to his home to safety. There, Khui informed that his memories of various gods were slowly fading from his memory, imploring him to help him remember. In this capacity, Bayek helped him to recover the idols of Egyptian gods Bastet, Horus and Thoth, which Khui placed together. A light subsequently engulfed Khui, turning into a personification of Amun-Ra in the form of Bayek.