56 selected
- Not filled in
- Obscure
- Obscuritas
- Oceanhorn
- Octopath Traveler
- Octopus
- Oddworld
- Odyssee
- Odyssey
- Of Orcs and Man
- Ogre Battle
- Oil panic
- Okami
- Olympische Spelen
- Omar Sharif Bridge
- One Piece
- Onechanbara
- Oni
- Onimusha
- Oninaki
- Online Chess
- Only on Xbox 360 & Windows
- Only on Playstation
- Only on PS3
- Only on Xbox
- Only on Xbox 360
- Only on Xbox 360 & Windows
- Open Season
- Operation Flashpoint
- Operation Serpens
- Operation Warcade
- OPM Demo DVD
- OPM2 Demo DVD
- Opus
- Ori and the Blind Forrest
- Orphen
- Othello (Reversi)
- Otogi
- Ottesei island
- Oure
- Out of Ammo
- Out Run
- Outcast
- Outcry
- Outland
- Outlast
- Outlaw
- Outlaw Golf
- Outlaws
- Outpost
- Outrun
- Over the Hedge
- Overblood
- overboard
- Overlord
- Overwatch
- Oxenfree