The Thunder Horse is a cryptid only seen in the video game The Secret Saturdays: Beasts of the fifth sun.
The Thunder Horse is a large, grayish, and dotted equine. This huge cryptid's hoof-beats were said to be the origin of thunder. This creature's indestructible hooves allow it run over spiked surfaces. This creature is also known for killing bison as a self defense. The early Indians of central-north America were shocked at the immense size of this beast. In the ice cavern level of the video game, Zak has to ride the thunder horse over-top the icicles.