Also haruspicy. The ancient Druidic, Etruscan and Roman practice of examining the entrails, mainly the liver (hepatoscopy), of sacrificial animals for purposes
of divination; frequent part of augury performed by a specialised priest, the Aruspex. Mention of it also occurs in the Old Testament (Ezekiel 21:21) in regard to practices of non-Hebrew tribes, including the Egyptians.
The practice ceased with the establishment of Christianity as the state religion of Rome but until then it was popular with people who could afford to sacrifice (the
animal was naturally eaten afterwards) and given great heed by emperors and generals. It may have lasted longer in north-western Europe which wasn't christianised until much later. In modern times, there's limited use of this practice in association with voodoo.
Some practitioners used human entrails and this widely illegal practice of (anthropomancy) is recorded as late as the fourth century CE but may have been part of the black arts in later times.