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- Obake no Q-tarÅ: WanWan Panic (Family Computer)
- Oishinbo (Family Computer, Nintendo DS)
- One Piece Grand Battle (Nintendo GameCube, PlayStation 2)
- One Piece (Game Boy Advance)
- One Piece: Gear Spirits (Nintendo DS)
- One Piece Grand Adventure (PlayStation 2, GameCube)
- One Piece Grand Battle! (PlayStation 2, PSone, GameCube)
- One Piece Grand Battle 3 (PlayStation 2, GameCube)
- One Piece Treasure Battle! (GameCube)
- One Piece: Pirates Carnival (PlayStation 2, GameCube)
- One Piece: Unlimited Adventure (Nintendo Wii)
- One Piece: Unlimited cruise:The Treasure Beneath the Waves (Nintendo Wii)
- One Piece: Unlimited cruise 2:Awakening Of A Hero (Nintendo Wii)
- One Piece: Kaizoku Musou (PlayStation 3 PS3)
- Ookiku Furikabutte - Honto no Ace ni Nareru kamo (Nintendo DS)
- Osu!! Karate Bu (Super Famicom)
- Ouran Koukou Host Club (PlayStation 2) (Japan only)
- Ouran Koukou Host Club DS (Nintendo DS) (Japan only)
Read more about this topic: List Of Video Games Based On Anime Or Manga