- "Should malice cling too strongly to your hearts, Isfet, the Evil One... shall smite the Goddess and condemn Yamu to a hundred seasons of darkness!"
- ―The High Priest of Sekhmet at the Festival of Sekhmet, 48 BCE[src]
Isfet, known as the Lord of Chaos or the Evil One, is an Egyptian personification of chaos, violence, ordeals, and disharmony. The antithetical counterpart to Ma'at, the goddess of truth, order, and harmony, Isfet is a primordial part of the world in Egyptian mythology.
He was regarded by the ancient Egyptians as a force of nature to be periodically fought and overcome so as to ensure the triumph of Ma'at and the preservation of the cosmic order. Accordingly, he was the subject of ritual, mock battles staged by the Egyptians in their festivals, such as the Festival of Sekhmet held in Yamu in 48 BCE, where actors portraying the goddess Sekhmet and the god Isfet engaged in a ceremonial fight to determine whether the former would protect them from the latter.
Role in the Festival of Sekhmet
A tradition of the Temple of Sekhmet in Yamu that began around 53 BCE was to host a ceremonial fight between actors of their patron goddess, Sekhmet, and Isfet during the Festival of Sekhmet. It was the belief of the locals that the outcome of this mock battle was determined by Sekhmet's own struggle against Isfet and that should the actor portraying her be defeated, this would indicate that Isfet had prevailed over Sekhmet, inaugurating a period of tribulations.
In 48 BCE, this grand event was promoted by the then High Priest of Sekhmet as a sacred ritual that had secured the safety of Yamu for centuries despite having only been a recent development. His deputy, Menehet implied to his friend the Medjay Bayek that such ceremonies served in part to attract tourism and wealth for the town and temple. To that end, the High Priest composed his own original tale of the legendary contest between Sekhmet and Isfet.
According to his story, Isfet was once Ma'at's husband, but in his gluttony, he tampered with the Scales of Judgment, feeding off the souls of hapless mortals. For this crime, Ma'at expelled him from the Hall of Justice. Unable to bear his hunger, he sought to return, only for the lion-goddess Sekhmet to bar his entry, sparking a violent battle that lasted for twenty days and nights before Sekhmet finally subdued him.
Hence, the spectacle staged at Yamu's Festival of Sekhmet was akin to a reenactment between two actors of this conflict, only that it was touted as a live mirror of Sekhmet's recurring fight against Isfet. Sensationalizing the event, the High Priest claimed that should Sekhmet's champion be defeated, it would be owing to the impurity of the locals' hearts, and Yamu would be forced to endure near a century of turmoil. 
Festival of Sekhmet of 48 BCE
At the Festival of Sekhmet in 48 BCE, the fighter cast to play as Sekhmet was an alcoholic by the name of Pamu. On the day of the event, Pamu was passed out drunk at the local tavern and failed to appear at the appointed time to prepare for his major role. Panicking, Menehet tasked the Medjay Bayek to find Pamu and bring him back in time for the ceremony.
Although Bayek was able to retrieve Pamu from the tavern, the man was in no state to competently participate in a bout, even a friendly one. As a result, Bayek offered his services as a substitute and was hurried to the stage at the last minute. Owing to his professional training as a Medjay, Bayek had defeated his opponent in the arena with ease, much to the delight of the priests and his audience. For his timely help, he was allowed to keep the Sekhmet costume as a reward.