Sphinxes are creatures from Ancient Greek and Egyptian mythology. They combine physical attributes of humans, birds, and lions. The sphinx, in Greek tradition, has the haunches of a lion, the wings of a great bird, and the face and breast of a woman. She is mythicised as treacherous and merciless. Those who cannot answer her riddle suffer a fate typical in such mythological stories, as they are killed and eaten by this ravenous monster. Unlike the Greek sphinx which was a woman, the Egyptian sphinx is typically shown as a man (an androsphinx). In addition, the Egyptian sphinx was viewed as benevolent in contrast to the malevolent Greek version and was thought of as a guardian often flanking the entrances to temples.
Sphinxes were the traditional enemies of centaurs. When contact with the Tin Isle was lost, and Centaurs were no longer able to import tin and thus to alloy copper into bronze, the sphinxes enjoyed a significant military advantage. They pressed this advantage and won a major victory over their foes in Asia Minor. This victory prompted the Centaurs to realize the severity of the crisis to which their tin shortage subjected them, and to mount several expeditions to attempt to secure sources of the metal.