| Region | Title | System | Version | Edition | Languages | Serial | Status |
|---|
 | Onimusha: Warlords | PS2 | 1.02 | Original, Platinum |    | SLES-50247 … | ![2 and more dumps from original media [!]](/images/status/green.png "2 and more dumps from original media [!]") |
 | Onimusha: Warlords | PS2 | 1.00 | Original, Greatest Hits | | SLUS 20018 … | |
 | Online Games: Dai Guru Guru Onsen
オンラインゲームズ 大ぐるぐる温泉 | PS2 | 1.01 | Original |  | SLPM 62195 | |
| Online Pro Wrestling
オンラインプロレスリング | PS2 | 1.03 | Original | | SLPM 65586 | |
| Only You: Rebel Cross
Ｏｎｌｙ Ｙｏｕ リベルクルス | PS2 | 1.03 | Original, Drama CD Tsuki | | SLPS 25150 … | |
| Onside Complete Soccer | PSX | | Original |  | SLES-00079 | |
| Onside Complete Soccer | PSX | Rev 1 | Original | | SLES-00079 | |
| OnSide Soccer | 3DO | | Unlicensed (oldergames, Good Deal Games Double Header! Two Game Set) | | | |
| Ooedo Fuusui Ingaritsu: Hanabi 2
大江戸風水因果律 花火２ | PSX | | Original | | SLPS 02814 | |
| Ooedo Renaissance
大江戸ルネッサンス | SS | 1.001 | Original | | T-9104G | |
| Oogami Ichirou Funtouki: Sakura Taisen Kayou Show "Beni Tokage" yori (Disc 1)
大神一郎奮闘記 ～サクラ大戦歌謡ショウ「紅蜥蜴」より～ | DC | 1.000 | Original, Sample | | HDR-0057 | |
| Oogami Ichirou Funtouki: Sakura Taisen Kayou Show "Beni Tokage" yori (Disc 2)
大神一郎奮闘記 ～サクラ大戦歌謡ショウ「紅蜥蜴」より～ | DC | 1.000 | Original, Sample | | HDR-0057 | |
| Ookami
大神 | PS2 | 1.03 | Original, PlayStation 2 the Best | | SLPM 66375 … | |
| Ookami Kakushi
おおかみかくし | PSP | 1.04 | Original | | ULJM 05413 | |
| Ookami-teki Monshou: Crest of Wolf
狼的紋章 クレスト・オブ・ウルフ | PCE | | Original | | HCD3044 | |
 | Ookami: Zekkeiban
大神 絶景版 | PS3 | 00.00 | Original, PlayStation 3 the Best, PlayStation 3 the Best (Reprint) | | BLJM 55061 … | |
| Oookuki
大奥記 | PS2 | 1.02 | Original | | SLPM 66441 | |
 | L'Open de Palm Springs | CDI | | Original, For Demonstration Only | | 812 0002 | |
| The Open Golf: History of Turnberry
ジ・オープンゴルフ History of Turnberry | PSX | | Original | | SLPS 00418 | |
 | Open Kart | PC | | I Videogiochi del "Giornalino" |  | | |
| Open Season | GC | | Original | | DL-DOL-GOSP-EUR | |
| Open Season | PSP | 1.00 | Original, PSP Essentials |     | ULES-00508 … | |
| Open Season | PS2 | 1.00 | Original |  | SLES-54310 | |
| Open Season | PS2 | 1.01 | Original | | SLES-54316 | |
| Open Season | PSP | 1.01 | Original | | ULES-00507 | |
| Open Season (Disc 1) | PC | 1.00 | Original | | 5004904-CD 1 | |
 | Open Season (Disc 2) | PC | 1.00 | Original | | 5004904-CD 2 | |
| Open Season (Disc 3) | PC | 1.00 | Original | | 5004904-CD 3 | |
| Open Season | PSP | 1.01 | Original | | ULUS 10152 | |
| Open Season | PS2 | 1.01 | Original | | SLUS 21467 | |
 | Open Season | XBOX | | Original | | US-097 | |
 | Open Season
Colegas en el Bosque | XBOX360 | | Original, ESA Foundation Holiday Bundle | | US-2024 | |
 | Operaciya "Plastilin" (Disc 1)
Операция "Пластилин" | PC | | 1C: Kollekciya igrushek |  | | |
| Operaciya "Plastilin" (Disc 2)
Операция "Пластилин" | PC | | 1C: Kollekciya igrushek | | | |
 | Operacja Pustynny Grom / The Partners | PC | | Covermount | | | |
| Operation | PC | | General Mills | | AM801R5 | |
| Operation Air Assault | PS2 | 1.01 | Original | | SLES-52572 | |
 | Operation Air Assault 2 | PS2 | 1.01 | Original | | SLES-54804 | |
| Operation Darkness
オペレーション・ダークネス | XBOX360 | | Original | | SU-2001 | |
| Operation Flashpoint: Cold War Crisis | PC | 1.0 | Original, Gold Edition | | MOPFCDEU00 | |
 | Operation Flashpoint: Cold War Crisis | PC | | The Games Collection | | | |
| Operation Flashpoint: Cold War Crisis | PC | 1.0 | Original | | MOPFCDUS00 | |
| Operation Flashpoint: Dragon Rising | PC | | Original | | MOFP2CDEU00 | |
| Operation Flashpoint: Dragon Rising | PS3 | 01.01 | Original, Promo | | BLES-00597 | |
| Operation Flashpoint: Dragon Rising | PC | 1.0 | Original | | MOFP2CDEU00 | |
| Operation Flashpoint: Dragon Rising | PS3 | 01.01 | Original | | BLJM 60152 | |
| Operation Flashpoint: Dragon Rising | PS3 | 01.01 | Original | | BLUS-30316 | |
| Operation Flashpoint: Dragon Rising | XBOX360 | | Original | | CM-2065 | |
| Operation Flashpoint: Elite | XBOX | | Original | | CM-090 | |
| Operation Flashpoint: Holodnaja vojna
Операция Flashpoint: Холодная война | PC | 1.46 | Original | | | |
| Operation Flashpoint: Red River | PS3 | 01.01 | Original | | BLES-01171 | |
| Operation Flashpoint: Red River | PC | 1.0 | Original | | MOFP3CDEU00 | |
| Operation Flashpoint: Red River | XBOX360 | | Original | | CM-2104 | |
| Operation Flashpoint: Red River | PS3 | 01.02 | Original, Codemasters the Best | | BLJM 60361 … | |
| Operation Flashpoint: Red River | PS3 | 01.01 | Original | | BLUS-30704 | |
| Operation Flashpoint: Red River | XBOX360 | | Original | | CM-2104 | |
| Operation WinBack | PS2 | 1.10 | Original | | SLES-50155 | |
| Operation WinBack 2: Project Poseidon | PS2 | 1.00 | Original | | SLES-54116 … | |
| The Operational Art of War: Century of Warfare | PC | | Original | | | |
| The Operative: No One Lives Forever | PS2 | 1.00 | Original | | SLES-50592 | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.0 | Original | | FXX08903223D1 | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.004 | Game of the Year Edition (BestSeller Series) | | S0026178 | |
| The Operative: No One Lives Forever (Disc 2) | PC | 1.0 | Original | | FXX08903223D2 | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.004 | Game of the Year Edition (BestSeller Series) | | JCPL11, S0026695 | |
 | The Operative: No One Lives Forever (Disc 1) | PC | 1.004 | Game of the Year Edition | | S0025036 | |
| The Operative: No One Lives Forever (Disc 2) | PC | 1.004 | Game of the Year Edition | | S0025037 | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.0.0.4 | Game of the Year Edition (Covermount) | | | |
| The Operative: No One Lives Forever (Disc 1)
ノーワンリブスフォーエバー | PC | 1.004, 1.004J | Original | | | |
| The Operative: No One Lives Forever (Disc 2)
ノーワンリブスフォーエバー | PC | 1.004, 1.004J | Original | | | |
| The Operative: No One Lives Forever | PS2 | 1.50 | Original | | SLUS 20028 | |
| The Operative: No One Lives Forever (Disc 1) | PC | | Game of the Year Edition | | | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.0 | Original | | | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.004 | Game of the Year Edition | | | |
| The Operative: No One Lives Forever (Disc 2)
In the Lounge with No One Lives Forever | PC | 1.0 | Original | | | |
| The Operative: No One Lives Forever (Disc 2) | PC | 1.004 | Game of the Year Edition, Game of the Year Edition (BestSeller Series), Game of the Year Edition (Covermount) | | JCPL11, S0026179, S0026696, S0026707 | |
| Operator's Side
オペレーターズ・サイド | PS2 | 1.02 | Doukonban, Doukonban: PlayStation 2 the Best | | SCPS 15038 … | |
| Opoona | WII | | Original | | RVL-RPOE-USA | |
| Option: Tuning Car Battle
オプション チューニングカーバトル | PSX | | Original | | SLPS 01207 | |
| Option: Tuning Car Battle 2
オプション チューニングカーバトル2 | PSX | | Original | | SLPS 01857 | |
| Option: Tuning Car Battle Spec R
オプション チューニングカーバトル スペックR | PSX | | Original | | SLPS 02587 | |
| Oracle no Houseki: Jewels of the Oracle
オラクルの宝石 | SS | 1.004 | Original | | T-1511G | |
| The Orange Box | PS3 | 01.00 | Original | | BLES-00153 | |
| The Orange Box (Disc 1) | PC | | Original |     | VAX07705811D | |
| The Orange Box | PS3 | 01.00 | Original | | BLES-00171 | |
| The Orange Box (Disc 1) | PC | | Original, EA Value Games | | VAD07705811D | |
| The Orange Box (Disc 2) | PC | | Original, EA Value Games | | VAD07705811D2 | |
| The Orange Box (Disc 1) | PC | | Original | | VAI07705811D | |
| The Orange Box (Disc 2) | PC | | Original | | VAI07705811D2 | |
| The Orange Box | XBOX360 | | Original | | EA-2063 | |
| The Orange Box (Disc 1) | PC | 4295 / 4539 | Rerelease |     | | |
| The Orange Box (Disc 2) | PC | 4295 / 4539 | Rerelease | | | |
| The Orange Box (Disc 2) | PC | | Original | | 985217 | |
 | The Orange Box
오렌지 박스 | PS3 | 01.00 | Original | | BLAS 50034 … | |
| The Orange Box (Disc 1) | PC | | Original, EA Classics | | 985207, VAE07705811D, VAE07705811D/ENG, VAE07707118D/ENG, VAX07705811D/AUS | |
 | The Orange Box
오렌지 박스 | XBOX360 | | Original | | EA-2063 | |
| The Orange Box (Disc 2) | PC | | Original, EA Classics | | VAE07705811D2/ENG, VAE07707118D2/ENG, VAX07705811D2, VAX07705811D2/AUS | |
| Orange Honey: Boku wa Kimi ni Koi shiteru
オレンジ♥ハニー 僕はキミに恋してる | PS2 | 1.02 | Original, Best Collection | | SLPS 25767 … | |
| Orange Pocket: Cornet
オレンジポケット －コルネット－ | DC | 1.004 | Original, Shokai Genteiban | | T-18707M, T-18708M | |
| Ore ga Kantoku da! Gekitou Pennant Race
オレが監督だ！ ～激闘ペナントレース～ | PS2 | 1.03 | Original | | SLPM 65005 | |
| Ore no Dungeon: Desire and Adventurous Spirit
己のダンジョン Ｄｅｓｉｒｅ ａｎｄ ａｄｖｅｎｔｕｒｏｕｓ ｓｐｉｒｉｔ． | PSP | 1.01 | Original | | ULJM 05167 | |
