Orochi is the main villain from The King of Fighters' 97. Fans consider him to be the easiest boss from the King of Fighters series, which is known for having some of the cheapest bosses from fighting games.
Orochi is a deity who serves Gaia, being the guardian of nature. He watched over nature since ancient times, creating a clan and forming the Hakkeshu, who were the eight strongest warriors of his clan. As mankind grew in numbers and populated most of the planet, nature started to become unbalanced. 1800 years ago, Orochi simply decided that humanity had to be exterminated, spreading chaos through the world. Humanity fought against him and his clan, and Orochi was defeated by the combined forces of the clans of Kusanagi, Yasakani and Yata, who used three sacred treasures to seal him away.
The Hakkeshu attempted to break the seal by pitting the three clans against each other. The Yasakani became mortal enemies of the Kusanagi, changing their name to Yagami. Goenitz, the recent leader of the Hakkeshu, started a plan to break the seal of Orochi. He fought a crime lord known as Rugal Bernstein, taking his right-eye and giving him a portion of Orochi power in hopes that he would become one of the Hakkeshu. Rugal hosted the King of Fighters tournament twice and was defeated by Kyo Kusanagi, so the Orochi power consumed him in the end. Chizuru Kagura, heir of the Yata clan, hosts the tournament again in hopes of convincing Kyo Kusanagi and Iori Yagami on giving up their vendetta and joining to defeat Orochi, but Goenitz interferes. Goenitz is defeated and disappears, so Yashiro Nanakase, another member of the Hakkeshu, hosts the next year tournament to gather enough energy to awaken Orochi, aided by his fellows Shermie and Chris. Yashiro succeeds, and Orochi possesses Chris's body, reshaping it to look older and tougher. Altough weakened from his seal, Orochi wants to resume his plan to wipe out humanity. Kyo, Iori and Chizuru join their forces and defeat Orochi, sealing him once again. After the defeat of Verse, Orochi managed to return in Hungary, however he was found and sealed away by the three sacred treasures.