Cryptozoology, Greek Folklore, Greek Myth, Mythological Creature Archive

Mythological Creature; Arion, a green maned, divine horse from Greek Mythology

According to greekmythology.com (I'll keep their hyperlinks so you can refer to their webpage for further research.) Arion was an immortal horse in Greek mythology, which was very fast and bred by the gods. According to a source, it also had the ability to speak.