Ama no Fuchigoma (天乃斑駒, lit. "heavenly spotted horse") is a mythical horse from a collection of Japanese folklore known as the Chronicles of Japan or Nihon-Shoki (日本書紀). In the mythology, Ama no Fuchigoma was ridden by the god Susanoo.
References
Ama no Fuchigoma Wikipedia(Text) CC BY-SA