Akuma no Oni

Akuma no Oni was a powerful oni summoned by Isawa Akuma. It was one of the Oni Lords, and was considered to be the most fearsome and powerful oni to ever come forth from Jigoku.

Creation
The oni was summoned by Isawa Akuma in 283 to answer the questions the Isawa had about the Underworld. The cunning demon began to have an incredible hatred for humanity and ended by stealing the shugenja's name, killing Akuma and advancing quickly in power. After freeing itself, the oni ravaged Gisei Toshi and destroyed the Council of Five in revenge on the Isawa. Possessed of an unsurpassed hatred of humans, Akuma's spawn are often found in any major Shadowlands assault.

Description
The oni has been described by Kuni Mokuna in his works as a "deadly being with elongated clutching arms tipped with razor-sharp claws". Its eyes are said to strike anyone with shear terror. Its three flailing tongues drip acidic mucus. Akuma stood approximately 28 feet tall and had acid for blood.

Kitsu Okura
Akuma's essence became trapped in a castle at the edge of the Lion Clan lands, where it was discovered by Kitsu Okura. The shugenja made a bargain with the demon, where in exchange for power and knowledge Okura would give up his soul as well as spread corruption among his Clanmates. Okura's new-found power was ironically instrumental in him eventually winning the position of Jade Champion, the leader of the hunt against corrupted magics in the Empire. Okura fell deeper into corruption during this time, eventually culminating in him giving his name to one of Akuma's spawn - creating Okura no Oni.

Death
Akuma faced it's spawn, Okura no Oni, at the Battle of Oblivion's Gate in 1133. Okura had been influenced by the honor of the Lion Clan, and turned against her father. Okura killed Akuma, banishing the Oni Lord back to Jigoku.

Thwarted Destiny
In the Realm of Thwarted Destiny, Akuma no Oni and Yakamo no Oni were confronted by the Shadow Dragon. The demons did not trust the dragon, and were preparing to attack it when the First Oni appeared.

War in the Heavens
Fu Leng brought Akuma no Oni with him when he waged war on Tengoku. There Akuma fought with the Fortune Bishamon.

Return to Rokugan
Sometime later in the twelfth century Daigotsu used the knowledge of Shokansuru to summon Akuma no Oni, but severed the Oni Lord's connection to Jigoku. If Daigotsu were to die Akuma would also die, and without hope of respawning the Oni Lord was compelled to follow Daigotsu's orders.