Oni

Onis (鬼, Oni) are a mysterious race of monstrous, supernatural creatures and the central antagonists of the Orient series, who took over Hi no Moto from humanity and opposed by the Bushi, who fight against their oppression.

Profile
150 years before the current timeline the mysterious creatures, Onis appeared and killed every one of the famous warring states commanders then took over Hi no Moto. More than a century later humans now under the rule of the Onis, revere and worship their masters as Gods, praying and even giving them offerings. Devotion to Onis runs deep amongst human societies as many dream of being able to serve the Oni. Ore mining is considered a great honor as Oni feed on crystals and metals, therefore being responsible for offerings to the Oni.

In truth Oni are despotic, cruel and merciless, viewing and using humans purely as slaves and discarding them or even eating them when they outlive their usefulness. Their grotesque appearance and vile nature vastly constrast with the divine, buddha-esque imagery depicted in statues and decorations which paint them in a much more virtuous light, which many humans view with the utmost grace and respect.

Oni rule humans with both an iron grip, false preaching and propaganda, having falsified history to portray the Bushi, their sole opposition, as deviants and cruel tyrants who abused and mistreated peasants for self-benefit while describing themselves as liberators and fair rulers. To add salt to injury, Oni law forces Bushi and their descendants to carry their sword at all times, as identification proof meant to encourage the population to actively discriminate against them both verbally and even physically, even going as far as being made to tie a chained iron ball to their swords as further humilliation. Bushi under Oni control are segregated from the rest of the population and made to live in poverty and perform tasks like being street cleaners, in what is meant to be a perpetual state of punishment and deriding, a subtle yet live proof that Oni are not as benevolent as they claim to be.

To further perpetuate the ruse, Oni themselves tend to seclude themselves from human view, helping nurture the falsehoods behind their positive traits while keeping humans docile and enamored with their image and the idea of serving directly under them. It is when humans are actually made to serve the Oni (like ore miners), when their mythology is all but entirely exposed as nothing more but a farce to maintain their oppressive rule. No longer having to keep up pretenses at this point, the Oni entirely abandon any restraint in favor of governing through power and fear, making it clear to humans that they are to serve them for life and be disposed of like trash when they are no longer useful.

The Oni also use some humans for other tasks such as helping manage slave camps, serving as enforcers of the Oni's will acting with derision towards opposition, even whiplashing other workers and being openly obedient and devoted in their tasks. Whether they are granted privileges or act out of fear, or possibly both is not entirely clear.

Overview
The Oni's primary diet is crystals and minerals, making humans into slave miners for the sole purpose of feeding. They are nonetheless entirely capable of eating humans just as well.

Weak Point
Oni's weak point is their horn, Shinkaku which is made of a really tough material. It cannot be slashed without a special weapon, called Kitetsuto. On the other hand every spot (except the Shinkaku) can be cut. When the horn is cut off the Oni dies and just Oni iron sand, Kitetsu remains.

Kishin (鬼神)
Kishins are the strongest type of Onis, the boss. It is said they are grotesque with the faces of devils and the power of gods. There are more than 100 Kishins in Hi no Moto' s territory.
 * Black Kishin (Rank Top1)
 * Yamata no Orochi (Green Kishin/Rank Top2 - 5??)
 * Engoku Tengu (?? Kishin/Rank ??)
 * Agyo-Ungyo (?? Kishin/Rank ??)

Small Oni (小鬼)
Small Oni can have various forms.