Exemplars of izbu compendia first appear in the old Babylonian period but it is not until the late second millennium that it is thought to have reached canonical form and exemplars of teratomantic texts from this era have been found in Assur and Babylon as well as further afield in Susa, Emar, Ugarit (in Ugaritic[1]) and Ḫattuša.
It was one of the works cited by the astrologer Marduk-šāpik-zēri as evidence of his learning in his letter to Aššur-bāni-apli in search of employment.
Its esoteric nature was emphasized by the royal astrologer Balasi, in his letter to the same king: Šumma izbu is difficult to interpret.
In common with the Sakikkū (SA.GIG), it arranges the malformations ištu muḫḫi adi šēpi, “from head to foot,” and in the color sequence: white, black, red, green–yellow, and variegated.
[4] For the most part, private omens concerned the fortunes of the bēl bīti, head of a household, or the owner of a flock or herd and related to life and death, health, general condition, relationship with the gods, social status, family and economic circumstances.