Echidna

Echidna a monster, half-woman and half-snake, who lives alone in a cave. She is the mate of the fearsome monster Typhon. Echidna is often referred to as the "Mother of Monsters". The reason being her unquenchable carnal attraction fo Typhon which produced many of the most horrifying creatures on Ambrosia.
Many adventurers in the inns of Hellas will tell you that, "You are not a hero if you haven't slain a daughter or some of Echidna".
Echidna is a great admirer of gems and for people brave enough to venture in her caves she is willing to grant them her dark powers in the form of her blood in exchange for these precious stones. Many heroes have tried to acquire said gems and met their death whilst trying.