You kinda missed the point with that, Its Symbolic to bayek and beliefs at the time, Hence why the assassins do it in the other games too. Example.. The Weighing of the Heart In the Duat, the Egyptian underworld, the hearts of the dead were said to be weighed against her single "Feather of Ma'at", symbolically representing the concept of Maat, in the Hall of Two Truths. This is why hearts were left in Egyptian mummies while their other organs were removed, as the heart (called "ib") was seen as part of the Egyptian soul. If the heart was found to be lighter or equal in weight to the feather of Maat, the deceased had led a virtuous life and would go on to Aaru. Osiris came to be seen as the guardian of the gates of Aaru after he became part of the Egyptian pantheon and displaced Anubis in the Ogdoad tradition. A heart which was unworthy was devoured by the goddess Ammit and its owner condemned to remain in the Duat.