Region | Title | System | Version | Edition | Languages | Serial | Status |
| O.D.T. | PSX | | Original | | SLUS-00698 | |
| O.D.T. | PSX | | Demo | | SLUS-90043 | |
| Obscure ObsCure | XBOX | | Original | | MI-009 | |
| Obscure ObsCure | PS2 | 1.00 | Original | | SLUS 20777 | |
| Obscure: The Aftermath ObsCure: The Aftermath | PSP | 1.00 | Original, Test Sample | | ULUS-10484 | |
| Obsidian (Disc 1) | PC | | Original, Complimentary Copy | | 11008 | |
| Obsidian (Disc 2) | PC | | Original, Complimentary Copy | | 11008 | |
| Obsidian (Disc 3) | PC | | Original, Complimentary Copy | | 11008 | |
| Obsidian (Disc 4) | PC | | Original, Complimentary Copy | | 11008 | |
| Obsidian (Disc 5) | PC | | Original, Complimentary Copy | | 11008 | |
| Oceans Below The Software Toolworks Presents ... Oceans Below | MAC | | Original | | 2198620-590001 / I 073100, CDRM1103420 | |
| Oceans Below | 3DO | | Original | | | |
| Odama | GC | Rev 1 | Original | | DL-DOL-GOOE-USA | |
| Oddworld: Abe's Exoddus (Play) | PC | | Original | | 04-15993CD2 | |
| Oddworld: Abe's Exoddus (Install) | PC | 2.0 | Original | | 04-15993CD1 | |
| Oddworld: Abe's Exoddus (Disc 1) | PSX | | Original | | SLUS-00710 … | |
| Oddworld: Abe's Exoddus (Disc 2) | PSX | | Original | | SLUS-00731 … | |
| Oddworld: Abe's Oddysee | PSX | | Original | | SLUS-00190 | |
| Oddworld: Abe's Oddysee | PSX | | Demo | | SLUS-90004 | |
| Oddworld: Abe's Oddysee | PC | 2.0 | Original | | 04-12608CD | |
| Oddworld: Abe's Oddysee | PSX | Rev 1 | Original, Greatest Hits | | SLUS-00190 | |
| Oddworld: Abe's Oddysee | PSX | Rev 2 | Greatest Hits | | SLUS-00190 | |
| Oddworld: Abe's Oddysee: New 'n' Tasty! | PS3 | 01.00 | Limited Edition | | BLUS-31621 | |
| Oddworld: Stranger's Wrath | XBOX | | Original | | EA-109 | |
| Oddworld: Stranger's Wrath HD | PS3 | 01.00 | Original | | BLUS-31620 | |
| Odell Down Under | PC | | Original, SoftKey | | POD544AE-CD | |
| Odin Sphere | PS2 | 1.00 | Original, Greatest Hits | | SLUS 21577 … | |
| Odin Sphere: Leifthrasir | PS3 | 01.01 | Original | | BLUS-31601 | |
| Odium ōdi·um | PC | | Original | | CD-W58-1104-0 | |
| ODS Robot Challenge | PC | 5.0.1r26 | Teacher's Edition | | | |
| Off-World Interceptor Extreme | PSX | | Original | | SLUS-00020 | |
| The Official Guide to Babylon 5 The Official Guide to J. Michael Straczynski's Babylon 5 | PC | | Original | | | |
| Official Sega Dreamcast Magazine: Special Edition Preview PC CD-ROM | PC | | | | | |
| Official U.S. PlayStation Magazine Demo Disc 01 | PSX | | | | SCUS-94189 | |
| Official U.S. PlayStation Magazine Demo Disc 02 | PSX | | | | SCUS-94198 | |
| Official U.S. PlayStation Magazine Demo Disc 03 | PSX | | | | SCUS-94210 | |
| Official U.S. PlayStation Magazine Demo Disc 04 | PSX | | | | SCUS-94211 | |
| Official U.S. PlayStation Magazine Demo Disc 05 | PSX | | | | SCUS-94212 | |
| Official U.S. PlayStation Magazine Demo Disc 06 | PSX | | | | SCUS-94213 | |
| Official U.S. PlayStation Magazine Demo Disc 07 | PSX | | | | SCUS-94214 | |
| Official U.S. PlayStation Magazine Demo Disc 08 | PSX | | | | SCUS-94215 | |
| Official U.S. PlayStation Magazine Demo Disc 09 | PSX | | | | SCUS-94216 | |
| Official U.S. PlayStation Magazine Demo Disc 10 | PSX | | | | SCUS-94217 | |
| Official U.S. PlayStation Magazine Demo Disc 100 | PS2 | 1.00 | | | SCUS 97452 | |
| Official U.S. PlayStation Magazine Demo Disc 101 | PS2 | 1.00 | | | SCUS 97453 | |
| Official U.S. PlayStation Magazine Demo Disc 102 | PS2 | 1.00 | | | SCUS 97454 | |
| Official U.S. PlayStation Magazine Demo Disc 103 | PS2 | 1.00 | | | SCUS 97531 | |
| Official U.S. PlayStation Magazine Demo Disc 104 | PS2 | 1.00 | | | SCUS 97532 | |
| Official U.S. PlayStation Magazine Demo Disc 105 | PS2 | 1.00 | | | SCUS 97533 | |
| Official U.S. PlayStation Magazine Demo Disc 106 | PS2 | 1.00 | | | SCUS 97534 | |
| Official U.S. PlayStation Magazine Demo Disc 107 | PS2 | 1.02 | | | SCUS 97535 | |
| Official U.S. PlayStation Magazine Demo Disc 108 | PS2 | 1.00 | | | SCUS 97536 | |
| Official U.S. PlayStation Magazine Demo Disc 109 | PS2 | 1.00 | | | SCUS 97537 | |
| Official U.S. PlayStation Magazine Demo Disc 11 | PSX | | | | SCUS-94218 | |
| Official U.S. PlayStation Magazine Demo Disc 110 | PS2 | 1.00 | | | SCUS 97538 | |
| Official U.S. PlayStation Magazine Demo Disc 111 | PS2 | 1.00 | | | SCUS 97539 | |
| Official U.S. PlayStation Magazine Demo Disc 112 | PS2 | 1.00 | | | SCUS 97540 | |
| Official U.S. PlayStation Magazine Demo Disc 12 | PSX | | | | SCUS-94219 | |
| Official U.S. PlayStation Magazine Demo Disc 13 | PSX | | | | SCUS-94275 | |
| Official U.S. PlayStation Magazine Demo Disc 14 | PSX | | | | SCUS-94276 | |
| Official U.S. PlayStation Magazine Demo Disc 15 | PSX | | | | SCUS-94277 | |
| Official U.S. PlayStation Magazine Demo Disc 16 | PSX | | | | SCUS-94278 | |
| Official U.S. PlayStation Magazine Demo Disc 17 | PSX | | | | SCUS-94279 | |
| Official U.S. PlayStation Magazine Demo Disc 18 | PSX | | | | SCUS-94280 | |
| Official U.S. PlayStation Magazine Demo Disc 19 | PSX | | | | SCUS-94281 | |
| Official U.S. PlayStation Magazine Demo Disc 20 | PSX | | | | SCUS-94282 | |
| Official U.S. PlayStation Magazine Demo Disc 21 | PSX | | | | SCUS-94429 | |
| Official U.S. PlayStation Magazine Demo Disc 22 | PSX | | | | SCUS-94430 | |
| Official U.S. PlayStation Magazine Demo Disc 23 | PSX | | | | SCUS-94431 | |
| Official U.S. PlayStation Magazine Demo Disc 24 | PSX | | | | SCUS-94432 | |
| Official U.S. PlayStation Magazine Demo Disc 25 | PSX | | | | SCUS-94433 | |
| Official U.S. PlayStation Magazine Demo Disc 26 | PSX | | | | SCUS-94434 | |
| Official U.S. PlayStation Magazine Demo Disc 27 | PSX | | | | SCUS-94435 | |
| Official U.S. PlayStation Magazine Demo Disc 28 | PSX | | | | SCUS-94436 | |
| Official U.S. PlayStation Magazine Demo Disc 29 | PSX | | | | SCUS-94437 | |
| Official U.S. PlayStation Magazine Demo Disc 30 | PSX | | | | SCUS-94438 | |
| Official U.S. PlayStation Magazine Demo Disc 31 | PSX | | | | SCUS-94499 | |
| Official U.S. PlayStation Magazine Demo Disc 32 | PSX | | | | SCUS-94583 | |
| Official U.S. PlayStation Magazine Demo Disc 33 | PSX | | | | SCUS-94591 | |
| Official U.S. PlayStation Magazine Demo Disc 34 | PSX | | | | SCUS-94593 | |
| Official U.S. PlayStation Magazine Demo Disc 35 | PSX | | | | SCUS-94596 | |
| Official U.S. PlayStation Magazine Demo Disc 36 | PSX | | | | SCUS-94599 | |
| Official U.S. PlayStation Magazine Demo Disc 37 | PSX | | | | SCUS-94614 | |
| Official U.S. PlayStation Magazine Demo Disc 38 | PSX | | | | SCUS-94617 | |
| Official U.S. PlayStation Magazine Demo Disc 39 | PSX | | | | SCUS-94622 | |
| Official U.S. PlayStation Magazine Demo Disc 40 | PSX | | | | SCUS-94628 | |
| Official U.S. PlayStation Magazine Demo Disc 41 | PSX | | | | SCUS-94630 | |
| Official U.S. PlayStation Magazine Demo Disc 42 | PSX | | | | SCUS-94631 | |
| Official U.S. PlayStation Magazine Demo Disc 43 | PSX | | | | SCUS-94634 | |
| Official U.S. PlayStation Magazine Demo Disc 43 | PSX | EDC | | | SCUS-94634 | |
| Official U.S. PlayStation Magazine Demo Disc 44 | PSX | | | | SCUS-94637 | |
| Official U.S. PlayStation Magazine Demo Disc 45 | PSX | | | | SCUS-94645 | |
| Official U.S. PlayStation Magazine Demo Disc 46 | PSX | | | | SCUS-94649 | |
| Official U.S. PlayStation Magazine Demo Disc 47 | PSX | | | | SCUS-94652 | |
| Official U.S. PlayStation Magazine Demo Disc 48 | PSX | | | | SCUS-94655 | |
| Official U.S. PlayStation Magazine Demo Disc 49 | PS2 | 1.00 | | | SCUS 97158 | |
| Official U.S. PlayStation Magazine Demo Disc 50 | PSX | | | | SCUS-94658 | |
| Official U.S. PlayStation Magazine Demo Disc 51 | PS2 | 1.00 | | | SCUS 97165 | |
| Official U.S. PlayStation Magazine Demo Disc 52 | PSX | | | | SCUS-94662 | |
| Official U.S. PlayStation Magazine Demo Disc 53 | PS2 | 1.00 | | | SCUS 97176 | |
| Official U.S. PlayStation Magazine Demo Disc 54 | PSX | | | | SCUS-94664 | |
| Official U.S. PlayStation Magazine Demo Disc 55 | PS2 | 1.00 | | | SCUS 97181 | |
| Official U.S. PlayStation Magazine Demo Disc 56 | PS2 | 1.00 | | | SCUS 97182 | |
| Official U.S. PlayStation Magazine Demo Disc 57 | PS2 | 1.00 | | | SCUS 97183 | |
| Official U.S. PlayStation Magazine Demo Disc 58 | PS2 | 1.00 | | | SCUS 97184 | |
| Official U.S. PlayStation Magazine Demo Disc 59 | PS2 | 1.00 | | | SCUS 97185 | |
| Official U.S. PlayStation Magazine Demo Disc 60 | PS2 | 1.00 | | | SCUS 97186 | |
| Official U.S. PlayStation Magazine Demo Disc 61 | PS2 | 1.00 | | | SCUS 97187 | |
| Official U.S. PlayStation Magazine Demo Disc 62 | PS2 | 1.00 | | | SCUS 97188 | |
| Official U.S. PlayStation Magazine Demo Disc 63 | PS2 | 1.00 | | | SCUS 97189 | |
| Official U.S. PlayStation Magazine Demo Disc 64 | PS2 | 1.00 | | | SCUS 97190 | |
| Official U.S. PlayStation Magazine Demo Disc 65 | PS2 | 1.00 | | | SCUS 97191 | |
| Official U.S. PlayStation Magazine Demo Disc 66 | PS2 | 1.00 | | | SCUS 97241 | |
| Official U.S. PlayStation Magazine Demo Disc 67 | PS2 | 1.00 | | | SCUS 97242 | |
| Official U.S. PlayStation Magazine Demo Disc 68 | PS2 | 1.00 | | | SCUS 97243 | |
| Official U.S. PlayStation Magazine Demo Disc 69 | PS2 | 1.00 | | | SCUS 97244 | |
| Official U.S. PlayStation Magazine Demo Disc 70 | PS2 | 1.00 | | | SCUS 97245 | |
| Official U.S. PlayStation Magazine Demo Disc 71 | PS2 | 1.01 | | | SCUS 97246 | |
| Official U.S. PlayStation Magazine Demo Disc 72 | PS2 | 1.00 | | | SCUS 97247 | |
| Official U.S. PlayStation Magazine Demo Disc 73 | PS2 | 1.00 | | | SCUS 97248 | |
| Official U.S. PlayStation Magazine Demo Disc 74 | PS2 | 1.00 | | | SCUS 97249 | |
| Official U.S. PlayStation Magazine Demo Disc 75 | PS2 | 1.00 | | | SCUS 97250 | |
| Official U.S. PlayStation Magazine Demo Disc 76 | PS2 | 2.01 | | | SCUS 97251 | |
| Official U.S. PlayStation Magazine Demo Disc 77 | PS2 | 1.00 | | | SCUS 97252 | |
| Official U.S. PlayStation Magazine Demo Disc 78 | PS2 | 1.01 | | | SCUS 97331 | |
| Official U.S. PlayStation Magazine Demo Disc 79 | PS2 | 1.00 | | | SCUS 97332 | |
| Official U.S. PlayStation Magazine Demo Disc 80 | PS2 | 1.00 | | | SCUS 97333 | |
| Official U.S. PlayStation Magazine Demo Disc 81 | PS2 | 1.00 | | | SCUS 97334 | |
| Official U.S. PlayStation Magazine Demo Disc 82 | PS2 | 1.00 | | | SCUS 97335 | |
| Official U.S. PlayStation Magazine Demo Disc 83 | PS2 | 1.00 | | | SCUS 97336 | |
| Official U.S. PlayStation Magazine Demo Disc 84 | PS2 | 1.00 | | | SCUS 97337 | |
| Official U.S. PlayStation Magazine Demo Disc 85 | PS2 | 1.00 | | | SCUS 97338 | |
| Official U.S. PlayStation Magazine Demo Disc 86 | PS2 | 1.00 | | | SCUS 97339 | |
| Official U.S. PlayStation Magazine Demo Disc 87 | PS2 | 1.01 | | | SCUS 97340 | |
| Official U.S. PlayStation Magazine Demo Disc 88 | PS2 | 1.01 | | | SCUS 97341 | |
| Official U.S. PlayStation Magazine Demo Disc 89 | PS2 | 1.00 | | | SCUS 97342 | |
| Official U.S. PlayStation Magazine Demo Disc 90 | PS2 | 1.00 | | | SCUS 97442 | |
| Official U.S. PlayStation Magazine Demo Disc 91 | PS2 | 1.00 | | | SCUS 97443 | |
| Official U.S. PlayStation Magazine Demo Disc 92 | PS2 | 1.00 | | | SCUS 97444 | |
| Official U.S. PlayStation Magazine Demo Disc 93 | PS2 | 1.01 | | | SCUS 97445 | |
| Official U.S. PlayStation Magazine Demo Disc 94 | PS2 | 1.00 | | | SCUS 97446 | |
| Official U.S. PlayStation Magazine Demo Disc 95 | PS2 | 1.00 | | | SCUS 97447 | |
| Official U.S. PlayStation Magazine Demo Disc 96 | PS2 | 1.00 | | | SCUS 97448 | |
| Official U.S. PlayStation Magazine Demo Disc 97 | PS2 | 1.00 | | | SCUS 97449 | |
| Official U.S. PlayStation Magazine Demo Disc 98 | PS2 | 1.01 | | | SCUS 97450 | |
| Official U.S. PlayStation Magazine Demo Disc 99 | PS2 | 1.00 | | | SCUS 97451 | |
| Official Xbox Magazine Game Disc 04 | XBOX | | Original | | IM-003 | |
| Official Xbox Magazine Game Disc 05 | XBOX | | Original | | IM-004 | |
| Official Xbox Magazine Game Disc 06 | XBOX | | Original | | IM-005 | |
| Official Xbox Magazine Game Disc 07 | XBOX | | | | IM-006 | |
| Official Xbox Magazine Game Disc 08 | XBOX | | Original | | IM-007 | |
| Official Xbox Magazine Game Disc 09 | XBOX | | Original | | IM-008 | |
| Official Xbox Magazine Game Disc 10 | XBOX | | | | IM-009 | |
| Official Xbox Magazine Game Disc 11 | XBOX | | Original | | IM-010 | |
| Official Xbox Magazine Game Disc 12 | XBOX | | | | IM-011 | |
| Official Xbox Magazine Game Disc 13 | XBOX | | Original | | IM-012 | |
| Official Xbox Magazine Game Disc 14 | XBOX | | Original | | IM-013 | |
| Official Xbox Magazine Game Disc 15 | XBOX | | | | IM-014 | |
| Official Xbox Magazine Game Disc 16 | XBOX | | Original | | IM-015 | |
| Official Xbox Magazine Game Disc 17 | XBOX | | Original | | IM-016 | |
| Official Xbox Magazine Game Disc 18 | XBOX | | Original | | IM-017 | |
| Official Xbox Magazine Game Disc 19 | XBOX | | Original | | IM-018 | |
| Official Xbox Magazine Game Disc 20 | XBOX | | Original | | IM-019 | |
| Official Xbox Magazine Game Disc 21 | XBOX | | Original | | IM-020 | |
| Official Xbox Magazine Game Disc 22 | XBOX | | Original | | IM-021 | |
| Official Xbox Magazine Game Disc 23 | XBOX | | | | IM-022 | |
| Official Xbox Magazine Game Disc 24 | XBOX | | Original | | IM-023 | |
| Official Xbox Magazine Game Disc 25 | XBOX | | Original | | IM-024 | |
| Official Xbox Magazine Game Disc 26 | XBOX | | Original | | IM-025 | |
| Official Xbox Magazine Game Disc 27 | XBOX | | Original | | IM-027 | |
| Official Xbox Magazine Game Disc 28 | XBOX | | Original | | IM-028 | |
| Official Xbox Magazine Game Disc 29 | XBOX | | Original | | IM-029 | |
| Official Xbox Magazine Game Disc 30 | XBOX | | Original | | IM-030 | |
| Official Xbox Magazine Game Disc 31 | XBOX | | Original | | IM-031 | |
| Official Xbox Magazine Game Disc 32 | XBOX | | Original | | IM-032 | |
| Official Xbox Magazine Game Disc 33 | XBOX | | Original | | IM-033 | |
| Official Xbox Magazine Game Disc 34 | XBOX | | Original | | IM-034 | |
| Official Xbox Magazine Game Disc 35 | XBOX | | Original | | IM-035 | |
| Official Xbox Magazine Game Disc 36 | XBOX | | Original | | IM-036 | |
| Official Xbox Magazine Game Disc 37 | XBOX | | Original | | IM-037 | |
| Official Xbox Magazine Game Disc 38 | XBOX | | Original | | IM-038 | |
| Official Xbox Magazine Game Disc 39 | XBOX | | Original | | IM-039 | |
| Official Xbox Magazine Game Disc 40 | XBOX | | Original | | IM-067 | |
| Official Xbox Magazine Game Disc 41 | XBOX | | Original | | IM-068 | |
| Official Xbox Magazine Game Disc 42 | XBOX | | Original | | IM-069 | |
| Official Xbox Magazine Game Disc 43 | XBOX | | Original | | IM-070 | |
| Official Xbox Magazine Game Disc 45 | XBOX | | Original | | IM-074 | |
| Official Xbox Magazine Game Disc 46 | XBOX | | Original | | IM-075 | |
| Official Xbox Magazine Game Disc 48 | XBOX | | Original | | IM-077 | |
| Official Xbox Magazine Game Disc 50 | XBOX | | Original | | IM-080 | |
| Official Xbox Magazine Game Disc 51 | XBOX | | Original | | IM-081 | |
| Official Xbox Magazine Game Disc 52 | XBOX | | Original | | IM-082 | |
| Official Xbox Magazine Game Disc 53 | XBOX | | Original | | IM-204 | |
| Official Xbox Magazine Game Disc 54 | XBOX | | Original | | IM-208 | |
| Official Xbox Magazine Game Disc 54e | XBOX360 | | | | SQ-2002 | |
| Official Xbox Magazine Game Disc 55 | XBOX | | | | IM-209 | |
| Official Xbox Magazine Game Disc 56 | XBOX | | Original | | IM-213 | |
| Official Xbox Magazine Game Disc 57 | XBOX | | Original | | IM-215 | |
| Official Xbox Magazine Game Disc 59 | XBOX | | Original | | IM-218 | |
| Official Xbox Magazine Game Disc 62 | XBOX | | Original | | IM-221 | |
| Official Xbox Magazine Game Disc 63 | XBOX | | | | IM-222 | |
| Official Xbox Magazine Game Disc 64 | XBOX | | | | IM-223 | |
| Official Xbox Magazine Game Disc 90 | XBOX360 | | | | IM-2082 | |
| Official Xbox Magazine Game Disc 91 | XBOX360 | | | | IM-2083 | |
| Offshore Tycoon | WII | | Original | | RVL-RXFE-USA | |
| Ogre Battle: Limited Edition | PSX | | Original | | SLUS-00467 | |
| Ohio Distinctive Software Vol. I | PC | | | | | |
| Okage: Shadow King | PS2 | 1.01 | Original | | SCUS 97129 | |
| Ōkami | WII | | Original | | RVL-ROWE-USA | |
| Ōkami | PS2 | 1.01 | Original, Greatest Hits | | SLUS 21115 … | |
| Olympic Soccer | PSX | | Original | | SLUS-00156 | |
| Olympic Soccer | 3DO | | Original | | FZ-SW0011 | |
| Olympic Summer Games | PSX | | Original | | SLUS-00148 | |
| Olympic Summer Games | 3DO | | Original | | FZ-SW0012 | |
| Omega Boost | PSX | | Original | | SCUS-94449 | |
| Omikron: The Nomad Soul | DC | 1.001 | Original | | T-36807N | |
| Omikron: The Nomad Soul (Disc 1) | PC | 1.0 | Original | | | |
| Omikron: The Nomad Soul (Disc 2) | PC | 1.0 | Original | | | |
| Omikron: The Nomad Soul (Disc 3) | PC | 1.0 | Original | | | |
| Ominous Horizons Ominous Horizons: A Paladin's Calling | PC | 1.0 | Original | | | |
| One | PSX | | Original | | SLUS-00469 | |
| One Piece Mansion | PSX | | Original | | SLUS-01406 | |
| One Piece: Unlimited World Red | PS3 | 01.00 | Day One Edition | | BLUS-31427 … | |
| One Unit Whole Blood | PC | 1.21 | Original | | 04-16459CD1 | |
| Oni | PC | 1.0 | Original | | | |
| Oni | PS2 | 1.20 | Original | | SLUS-20064 | |
| Onimusha 2: Samurai's Destiny | PS2 | 1.03 | Original | | SLUS-20393 | |
| Onimusha 3: Demon Siege | PS2 | 1.01 | Original | | SLUS-20694 | |
| Onimusha: Blade Warriors | PS2 | 1.01 | Original | | SLUS-20710 | |
| Onimusha: Dawn of Dreams (Disc 1) | PS2 | 1.02 | Original | | SLUS-21180 | |
| Onimusha: Dawn of Dreams (Disc 2) | PS2 | 1.02 | Original | | SLUS-21362 | |
| Onimusha: Warlords | PS2 | 1.00 | Original, Greatest Hits | | SLUS-20018 … | |
| Online Start-Up Disc 4.0 | PS2 | 1.00 | | | SCUS-97357 | |
| Online Start-Up Disc 4.0: Broadband Only | PS2 | 1.02 | Bundled with PS2 | | PBPX 95248 … | |
| Online Start-Up Disc v3.0 | PS2 | 1.01 | | | PBPX-95242 | |
| Online Start-Up Disc v3.0 | PS2 | 1.01 | | | SCUS 97425 | |
| Online Start-Up Disc v3.5: Broadband Only | PS2 | 1.00 | Original | | PBPX 95247 | |
| OnSide Soccer | 3DO | | Unlicensed (oldergames, Good Deal Games Double Header! Two Game Set) | | | |
| Open Season | XBOX360 | | Original, ESA Foundation Holiday Bundle | | US-2024 | |
| Open Season | PSP | 1.01 | Original | | ULUS 10152 | |
| Open Season | PS2 | 1.01 | Original | | SLUS 21467 | |
| Operation | PC | | General Mills | | AM801R5 | |
| Operation Flashpoint: Cold War Crisis | PC | 1.0 | Original | | MOPFCDUS00 | |
| Operation Flashpoint: Dragon Rising | PS3 | 01.01 | Original | | BLUS-30316 | |
| Operation Flashpoint: Gold Upgrade | PC | 1.30 | Original | | MOFUCDUS00 | |
| Operation Flashpoint: Red River | PS3 | 01.01 | Original | | BLUS-30704 | |
| Operation Flashpoint: Resistance | PC | 1.75 | Original | | MOFRCDUS00 | |
| The Operative: No One Lives Forever | PS2 | 1.50 | Original | | SLUS 20028 | |
| 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) | PC | 1.0 | Original | | | |
| Opoona | WII | | Original | | RVL-RPOE-USA | |
| The Orange Box | PS3 | 01.00 | Original | | BLUS-30055 | |
| The Orange Box (Disc 2) | PC | | Original | | 985217 | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 1) | PC | 1.0 | Original | | OTA744AE-CD1 | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 2) | PC | | Original | | OTA744AE-CD2 | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 3) | PC | | Original | | OTA744AE-CD3 | |
| The Oregon Trail 4th Edition (Disc 1) | PC | 1.1 | Rerelease | | OTF744BE-CD1 | |
| The Oregon Trail 4th Edition (Disc 2) | PC | 1.1 | Rerelease | | OTF744BE-CD2 | |
| The Oregon Trail 4th Edition (Disc 3) | PC | 1.1 | Rerelease | | OTF744BE-CD3 | |
| The Oregon Trail 5th Edition: Adventures Along the Oregon Trail | PC | 1.0 | Original | | 380859-CD | |
| The Oregon Trail 5th Edition: Adventures Along the Oregon Trail | PC | 1.1 | Rerelease, Southwestern School Set | | 380859B-CD | |
| Oregon Trail II | PC | 1.3 | Smart Saver | | 381032-CD/i401ha | |
| Oregon Trail II | PC | 1.31 | Rerelease | | HCD744BE-CD | |
| Oregon Trail II | PC | 1.31 | Rerelease | | #HCD744AE-CD | |
| Oregon Trail II: 25th Anniversary Limited Edition | PC | 1.3 | Original, SoftKey | | #OTR744AE-CD | |
| The Oregon Trail | WII | | 40th Anniversary Edition | | RVL-SORE-USA-B0 | |
| The Oregon Trail | PC | 1.2 | Original | | #HCD706 | |
| The Oregon Trail | PC | 1.2 | Original | | #HCD706 | |
| The Original Links | PC | | Solid Gold Edition | | | |
| Orphen: Scion of Sorcery | PS2 | 1.00 | Original | | SLUS-20011 | |
| Otogi: Myth of Demons | XBOX | | Original | | FS-002 | |
| Out of This World | 3DO | | Original | | | |
| Out of This World | 3DO | RE | 3DO Maniac Pack | | | |
| Outcast (Disc 1) | PC | | Original | | 42831-9110TC | |
| Outlaw Golf 2 | PS2 | 1.02 | Original | | SLUS 21030 | |
| Outlaw Golf: Holiday Golf | XBOX | | Original | | SS-005 | |
| Outlaw Tennis | PS2 | 1.01 | Original | | SLUS 21190 | |
| Outlaw Volleyball Remixed | PS2 | 1.02 | Original | | SLUS 21049 | |
| Outlaws (Disc 1) | PC | 1.0 Build 3 | Original | | 9511830 | |
| Outlaws (Disc 1) | PC | 1.0 Build 3 | Bundle Version Diamond OEM | | 644430 | |
| Outlaws (Disc 1) | PC | 2.0 | Rerelease | | 9511830 | |
| Outlaws (Disc 1) | PC | 2.0 | Rerelease | | 9511830 | |
| Outlaws (Disc 2) | PC | 1.0 Build 3 | Original | | 9511831 | |
| Outlaws (Disc 2) | PC | 2.0 | Rerelease | | 9511831 | |
| Outlaws (Disc 2) | PC | 2.0 | Rerelease | | 9511831 | |
| Outpost | PC | | Original | | S725430 | |
| Outpost | PC | 1.5 | Rerelease, Sierra Originals | | | |
| Outpost 2: Divided Destiny | PC | 1.2.0.5 | Original | | | |
| OutRun 2006: Coast 2 Coast | PS2 | 1.01 | Original | | SLUS 21274 | |
| OverBlood | PSX | | Original | | SLUS-00464 | |
| Overlord II | PS3 | 01.01 | Original | | BLUS-30317 | |
| Overlord: Raising Hell | PS3 | 01.00 | Original | | BLUS-30143 | |
| Overwatch | PC | | Game of the Year Edition, Legendary Edition | | 73052010US, S7302210 | |