How O-Ren joined the Tourney
It is presumed that her very early childhood was untroubled as little is known about her infancy. Her father was a Sergeant Major in the United States Marine Corps and her mother was a faithful housewife.
However, at the innocent age of nine, her life had forever changed when her home was intruded by assassins led by the ruthless crime boss, Matsumoto, Japan's cruelest Yakuza boss.
Whilst hiding under the bed for protection, young O-Ren witnessed her father, a brave man and skilled martial artist, disarm and kill two of Matsumoto's kumi-in. Although he fought fiercely and valiantly, his blind rage clouded his focus, and was subsequently caught off-guard when Matsumoto's right hand man, Riki, surprised him from behind and thrust a katana through his heart.
Immediately after her father's death, Matsumoto dragged her mother and threw her on the bed. Riki handed him the katana, Matsumoto personally executed Mrs. Ishii himself. Afterwards, the mob made a hasty departure. Riki, acting quickly to cover up the evidence of that night's horrific events, set the house ablaze.
Thankfully, despite her emotional state, O-Ren noticed the fire and managed to escape. As a result of witnessing the killings at such a young age, she was left psychologically and emotionally traumatized which fuels revenge.
With her childhood and loved ones having been ripped away from her, she became obsessed with exacting revenge against Matsumoto and avenging her parents by any means necessary.
After spending two years training, O-Ren, now aged eleven and knowing that Matsumoto was a pedophile, lured him into a compromising position by disguising herself as an innocent school-girl. She then used a sword to dig deep into Matsumoto's gut, applying such intense pressure that his teeth cracked while she asked him if he remembered her before disemboweling him. The sheer force of the bleeding killed Matsumoto instantly and the entire room was nearly drenched in his blood with O-Ren being covered in it.
Soon after killing the boss, O-Ren used Matsumoto's corpse as a shield and hid under the bed. Two of his henchmen attempted to shoot her but she evaded them and used her Desert Eagle magnum to blow off the henchmen's knees before her second and final shots decapitated both of them instantly. Decapitation would later become her preferred method of killing, not just of enemies, but henchmen who were rude enough to question her past and mixed heritage.
Nine years later, at the age of twenty, O-Ren had become one of the top female assassins in the world and was seen assassinating a Latin American political figure with just a single shot from her position of a rooftop.
Five years later and aged twenty-five, O-Ren was a member of the Deadly Viper Assassination Squad and took part in the vicious attack against the bride at her wedding rehearsal, helping to kill 10 (though it was really only 9, considering The Bride survived) innocent people and being partly responsible for putting the Bride into a coma.
About a year after the Massacre, Bill fully supported O-Ren "financially and philosophically" in her power struggle with the other Yakuza clans over who would rule vice in the city of Tokyo. She eventually becomes, what the Bride calls "Queen of Tokyo's underworld".
As "Queen of Tokyo's underworld", O-Ren had learned of brave warriors far out into the future. She sought out Marty McFly to make her a time gateway that will allow her access to any world for sport.
Character Select Screen Animation
O-Ren stands with her sheathed katana at her right.
After the announcer calls her name
O-Ren pulls out her katana and swings it and the scabbard as the camera zooms then says "You didn't think it was gonna be that easy, did you?"
Momokuteki Zan (Neutral)
O-Ren sets her katana into its scabbard and dashes forward with a slash. Nothings ot happen if it hits, but then the opponent is cut away.
Senryu Ha (Side)
O-Ren rapidly thrusts her katana then rushes through swinging her scabbard down.
Kozan Shosen (Up)
O-Ren jumps into the air swinging her katana three times then bashes her scabbard.
Hana Shunko (Down)
O-Ren holds her katana and scabbard out. If anyone tries to hit her, she moves back and forth hitting with her scabbard.
Fukushū Kokoro ni Moemashita (Hyper Smash)
O-Ren readies her katana and dashes forward. If she makes contact, she rapidly cuts through and nothing appears to happen. She then sheathes the katana and cuts appear on the opponent and blow him/her away.
Ryo O Satsugai (Final Smash)
O-Ren positions her sword above her, then does two slashes. If she hits, she then follows by doing a set of fifteen slashes, then finishes by kicking the opponent, leaving him/her in bloodied pieces, taking a life from the stock.
- O-Ren sits in a meditation and sheathes her katana then says "Swords, however, never get tired."
- O-Ren does two swings with her sword scabbard then pierces her katana and says "Is that even your... best shot?"
- O-Ren does three spinning slashes, then swings her scabbard and does a diagonal slash saying "I must say, you really worth bone picking."
O-Ren jumps out of her limo and pulls out her katana then holds it and her scabbard saying " You might not be able to fight like a samurai, but you can at least die like a samurai."
- O-Ren's rival is a young local man from Hill Valley named Marty McFly and her second rival is a Crunchem Hall student with a bright personality, Matilda Wormwood.
- O-Ren Ishii shares her English voice actress with Viper, Shelby Woo, Silvermist and the Suchomimus.
- O-Ren Ishii shares her German voice actress with Aayla Secura.
- O-Ren Ishii shares her Arabic voice actress with Velma Dinkley, Cher and Paint Roller.