After Medunamun's death at the hands of the Medjay Bayek of Siwa, Menkhtu took on Medunamun's mantle of The Ibis, calling himself as "The Ibis Reborn". Posing as Medunamun, he formed a sect from the remnants of the Order of the Ancients in Egypt and attempted to gain control.
In 46 BCE, Menkhtu's acts caught the attention of the Hidden Ones, a group of Proto-Assassins founded by Bayek, who sought to uncover his real identity. Their investigations led them to a remote temple in Haueris Nome, where Menkhtu had stationed a decoy of himself. The decoy was killed however and the Hidden Ones advanced. The Hidden Ones then eliminated three more decoys in the White Desert. In the meantime, Menkhtu was under the Great Pyramid of Giza trying to break into the ancient Isu complex Khesesh Em Sesh Em Eeneb.
The Hidden Ones eventually caught up to Menkhtu, in time to see him trying to decipher the vault pedestal. Angered that the temple would not reveal its secrets to him, Menkhtu faced the Hidden Ones and engaged them in combat. However, they proved too strong for him and he was killed. After his death, his identity was revealed and the rumors that the Ibis had been reborn were dispelled.