This item appears on the headdress of Khonsu, and this entity was the loser of a bet that extended the year to 365 days.
The Book of the Two Ways describes how the souls of the dead would go to the "Mansion" of this. A heart-eating god of this domain appears in the Cannibal Hymn to help the king slay his enemies. An ancient, obscure god with this domain is named Iah. In one tale, an object associated with it was offered to Osiris, who ate it to come (*) back to life. That object, which was restored after being torn out in a fight, was represented by the left Wadjet eye. This item appears on the headdress of Khonsu, and this entity was the loser of a bet that extended the year to 365 days. For 10 points, name this object which appears on the headdress of Thoth and his Ibis bill as a crescent shape.
The Book of the Two Ways describes how the souls of the dead would go to the "Mansion" of this.
{Moon} [prompt on the left eye of Horus]