The Spark Beast is first encountered in Shinshu Field (100 years ago). It attacks Chibiterasu using the same methods as the Fire Beast, Ice Beast, and Death Beast, being the Lightning member of the Beast demon group. It is a large blue horse with what appears to be scales on its neck and head. It has a prominent bright yellow mane and tail and a pair of grey horns on its head. On its back is a pair of golden wheels, which light up with Lightning when the Spark Beast prepares to attack.
The Spark Beast was formed from lightning bolts that appeared from dark clouds in cursed zones. It can not be fought with conventional weapons, but has poor eyesight, so much so that a strong wind would trip it. It was the source of the lightning bolt that split Konohana.
"The dark clouds lurking above the cursed zones created lightning bolts that
took on beastly form.
The bolt that split the sacred tree in Kamiki Village
was likely the work of this vile beast.
Those who have fought it with conventional weapons were burned to ashes.
Its vision is not good, and a strong wind could trip it up."
The Spark Beast has a number of attacks, and only a few opportunities to attack it while it is weak. When it rears back, it will stomp the ground, which is an easy attack to dodge. If it does not rear back, but stays on the ground, it will launch three bolts of Lightning, which can be dodged best while beside or behind the Spark Beast. If it enters the air and then darts around, it will strike the ground where Chibiterasu is, and must immediately have Galestorm used on it to stun it. If it begins to run around the sides of the battle area, it can be knocked down with Galestorm, which will also stun it. The Providence Crystal or a Glaive are best used against it, and offensive Celestial Brush techniques also work well. Once finished, its Floral Finisher is Galestorm.
- Raijū (Thunder Beast) is a name of a yokai with various different types with most commonly depicted as weasel or wolf like appearances. Nue is also occasionally considered as a type of Raijū.
- Despite the horse demons are considered to be Sacred beasts(「霊獣」?; Reijū), they are antagonists in this series.