Oh-Oni

The Oh-Oni (大鬼, Dai Oni) is a fictional character in the manga series of Shaman King. It is a Oni that can be summoned by Kyōyama Anna and her son Asakura Hana.

About
A gigantic red Oni, it is by far the most humanoid Oni ever seen. It wears a white shirt and has a glowing green face on its torso. There are two known instances where one has been summoned. One has been created by Kyōyama Anna when she unwittingly used her uncontrollable Reishi (霊視) power to make a Naka-Oni evolve into an Oh-Oni. Another was summoned directly by Asakura Anna due to a power given to him Asakura Hao were he, in a state of near death, goes into a trance and summons various sizes of Onis to defend himself.

The one created by Anna have shown intelligence and a personality. Though it has a sadistic behavior it speaks in a calm tone and even calls Anna its mother. This Oh-Oni was also able to regenerate and evolve by feasting on other Onis and spirits, where it gained a thick mustache and a pointy collar. It later becomes Saigan Sati's follower and acts in a more kind and friendly way.

Abilities and Powers
As an Oni created from at least 1080 worries, hopes, and prayers, the Oh-Oni is very powerful. It's intelligence was high enough for it to be able to speak human language and according to Matamune it has a speed as great as an arrow and it's strength is as strong as a hundred bulls. The souls within it, are connected by a chain of resentment giving it an infinite power.

Attacks


 * Oni-Daiko: An attack that sends thousands of small Oni, from his cut down arm, to attack the opponent in a very violent way.

Past
The Oh-Oni appears when when Yoh takes Anna out to celebrate the New Years and she is exposed to all the thoughts of the people around her. Though she at first only create a Naka-Oni it quickly evolves into the Oh-Oni. This new Oh-Oni was far beyond anything Yoh and even Matamune, who arrives to help, could handle.

Eventually, Matamune uses most of his Furyoku to impale the Oh-Oni's arm, but the Oh-Oni rips it off before Matamune can destroy him with Furyoku. Roaring in pain, the Oh-Oni grabs Anna and leaps to the very top of the mountain. There, he absorbs other spirits and other Oni to to regenerate his arm. He is only defeated when Matamune sacrifices his cat form to unite with Yoh and grant him the last of his Furyoku. With Matamune's last bit of Furyoku, Yoh defeats the Oh-Oni, who also begins to lose corporeal form when Anna begins to reveal her love for Yoh. He disappears, but not before making one last attack at his "mother" which Yoh deflects, and the Oh-Oni is sent to Hell.

Shaman Fights Second Round
When Yoh is sent to to train Hell by Lady Sati, the Oh-Oni appears before him opens the gate of Hell for Yoh, welcoming him with a strangely calm and kind personality. He reveals he now serves Lady Sati for all eternity, and leads Yoh to his training area, where he leaves him on his own. Before he leaves, the Oh-Oni smiles and asks Yoh to take care of his "mother".

Invading the Plants
The Oh-Oni, together with the Cho-Oni, Asakura Yohken and Mosuke appeared within the Great Spirit as the escorts of Hao's mother, Asanoha Douji.

Flowers
When Ichihara Ryuji almost killed Asakura Hana by fracturing his skull he went into a trance and began summoning Oni at random to attack Ryuji and Asakura Luca. As Luca destroyed all the Onis he summoned, Hana began chanting and summoned bigger Onis until finnaly he summoned a single Oh-Oni that landed an attack on Luca's Over Soul before it too was destroyed. In response Hana gathered the regenerating remains of his Onis to create a Dark-Oni that was finally able to defeat Luca.

Anime/Manga Difference
Due to Anna and Yoh's past never being mentioned, Oh-oni is never seen in the Anime.

Trivia

 * The Oh-Oni's bakai bones were used, by Asakura Kino, to create the 1080 beads that Anna uses for her Itako rituals.
 * Oh-Oni appears as a boss in the video game Shaman King: Master of Spirits 2. Because the game was based on the English version of the anime, which Oh-Oni doesn't appear in, he is colored blue, but if hit enough, he well turn red and change name to "Great Ogre".