Snakes on a "plain?" Those just sound like regular ol' ground-dwelling snakes.
Wikipedia: "Götterdämmerung (help·info) (Twilight of the Gods) is the last in Richard Wagner's cycle of four operas titled Der Ring des Nibelungen (The Ring of the Nibelung, or The Ring for short)... The title is a translation into German of the Old Norse phrase Ragnarök, which in Norse mythology refers to a prophesied war of the gods that brings about the end of the world... The term Götterdämmerung is occasionally used in English, referring to a disastrous conclusion of events."
HOLY CRAP THAT SOUNDS AWESOME I WANT TO SEE THAT MOVIE.