Region | Title | System | Version | Edition | Languages | Serial | Status |
| Oddworld: Abe's Exoddus (Play Disc) | PC | 2.0 | Original | | | |
| Oddworld: Abe's Exoddus (Install Disc) | PC | 2.0 | Original | | | |
| Official Formula 1 Racing | PC | | Original | | | |
| 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 | | | |
| Open Season (Disc 1) | PC | 1.00 | Original | | 5004904-CD 1 | |
| 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: Gold Upgrade | PC | 1.30 | Original | | MOFUCDUS00 | |
| Operation Flashpoint: Gold Upgrade | PC | 1.30 | Original, Gold Edition | | MOFUCDEU00, MOFUCDUS00 | |
| Operation Flashpoint: Holodnaja vojna Операция Flashpoint: Холодная война | PC | 1.46 | Original | | | |
| Operation Flashpoint: Resistance | PC | 1.75 | Original | | MOFRCDEU00 | |
| Operation Flashpoint: Resistance | PC | 1.75 | Original | | MOFRCDUS00 | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.0 | Original | | FXX08903223D1 | |
| 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 1) | PC | 1.0 | Original | | | |
| Outcast (Disc 2) | PC | | Original | | OUTCAPC52G/A2 | |
| ObsCure | PC | | Original | | 71902134 | |
| ObsCure II | PC | 1.0.0.0 | Original | | | |
| The Orange Box (Disc 1) | PC | | Original | | VAX07705811D | |
| The Orange Box (Disc 1) | PC | | Original | | VAI07705811D | |
| The Orange Box (Disc 2) | PC | | Original | | VAI07705811D2 | |
| The Orange Box (Disc 2) | PC | | Original | | 985217 | |
| The Orange Box (Disc 1) | PC | | Original, EA Classics | | 985207, VAE07705811D, VAE07705811D/ENG, VAE07707118D/ENG, VAX07705811D/AUS | |
| The Orange Box (Disc 2) | PC | | Original, EA Classics | | VAE07705811D2/ENG, VAE07707118D2/ENG, VAX07705811D2, VAX07705811D2/AUS | |
| OutRun 2006: Coast 2 Coast | PC | | Gamer's Choice | | THQ70690 | |
| OutRun 2006: Coast 2 Coast | PC | 1.0 | Original | | SEGA-PC029 | |
| OutRun 2006: Coast 2 Coast | PC | 1.00.0000 | Serie Maxima II | | SEGA-PC029 | |
| OutRun 2006: Coast 2 Coast | PC | | eXtra Klasyka XK HIT | | TS OCC PL | |
| Overlord | PC | 1.2 | Original | | | |
| Ori and the Blind Forest: Definitive Edition | PC | 5.3.2.9582331 | Limited Edition | | | |
| Outward | PC | | Day One Edition | | 1024669LAINT, 103699 | |
| Overwatch | PC | | Game of the Year Edition, Legendary Edition | | 73052010US, S7302210 | |
| Overwatch | PC | | Origins Edition | | | |