The Quick Intro:

Its appararance is the body and mane of a strong horse with the head of a bull. According to research it inhabits the North Region of the Republic Macedonia. It has an unussual deffence: It defendeds itself by emitting fire dung that could cover up to 600 yards ( 550 m ) in length.

More Detail:

The beast was described by Pliny the Elder as having the general appearance of a bull, but had the mane of a horse, horns curved back, and a neck a bit longer than that of the avarage bull. Its horns weren't built for fighting, instead its main defense was his fiery skunk-like attack. It is said that if it was attacked it would run away, leaving behind its trail of fire dung. This fire dung attack could set fire to trees and shrubs and of course scorch the fire of hunting dogs if they were unlucky enough to touch it.

This creature, as rare as some may find it, has actually quite the references to it. It has more than a dozen manuscripts that reference it. Some suggest that it had some resemblance to the European-Bison (which went extinct in 1919, but was reintroduced in Poland's forests and other places).