Blight is a demon warrior that has the power to spread plagues through an enchanted fog.
It appears as a walking suit of armor impaled with countless blades and arrows without any body, but it is actually possessed by the demon blade Goldnail, which it wields. This blade was drenched in the blood of its wielders' adversaries in numerous wars, and eventually became a demon and gained sentience.
Blight somehow came to Sei'an City and shrunk itself to fit in the stomach of the Emperor, spreading disease through the city with its unnatural fog, at Ninetails's command. Amaterasu and Issun eventually found the demon and defeat it, clearing up Sei'an City of the demonic fog. Blight's dark spirit then flew away and entered the Ark of Yamato, where it would have to be defeated again.
- Blight's helmet resembles the helmets on Orochi's heads, although Blight's helmet has a fog emblem and does not have a kanji symbol for its element on it.
- The blade that controls Blight, Goldnail, looks similar to the Yamato, the ōkatana that belonged to Vergil from the Devil May Cry series. Both blades have a golden circular guard, and possess magical properties. Additionaly, Goldnail can summon a circle of swords around Blight, similar to how Vergil has his "Summoned Swords" ability, which enables him to fire spectral blades. Also, Blight's swords circles bears very strong resemblances to Vergil's Spiral Sword, which is an extension of the Summoned Swords technique, in which Vergil creates a barrier of countless swords that surrounds his body.
- Blight's existence is based off the folklore of Tamamo-no-Mae in which he represents the illness that the priestess Tamamo-no-Mae planted on Emperor Konoe in order to take over the throne.