Polideukes, in greek mythology is Greek horse god. It was one of the Dioskouroi twins, the other being Kastor.
Traditionally they together were associated with a Spartan cult from whence they originated. Most p`robably the pair was derived from from the Indo-European model of the Asvins in the Vedic texts; Kastor being mortal while Polydeukes was immortal.
In battle Kastor is mortally wounded, but, even in death, the two brothers are inseparable.
They rescue individuals from distress and danger, especially at sea, and are thought to be embodied in the electrical discharges known as St. Elmo’s Fire. A.G.H.
Jordan, Michael, Encyclopedia of Gods, New York, Facts On File, Inc. 1993, p. 206