According to the Song dynasty history book Lushi (路史), Chiyou's surname was Jiang (姜), and he was a descendant of Yandi. According to legend, Chiyou had a bronze head with metal foreheads. He had 4 eyes and 6 arms, wielding terrible sharp weapons in every hand. In some sources, Chiyou had certain features associated with : his head was that of a bull with two horns, although the body was that of a human. He is said to have been unbelievably fierce, and to have had 81 brothers. Historical sources often described him as 'cruel and greedy', as well as 'tyrannical'. Some sources have asserted that the figure 81 should rather be associated with 81 clans in his kingdom.