| Name | # Files | Name | # Files | Name | # Files | ||
|---|---|---|---|---|---|---|---|
| Oath | 1 | Obitus | 1 | Obliterator | 1 | ||
| OBY1 | 1 | Odyssey | 1 | OhNoMoreLemmings | 1 | ||
| OilImperium | 1 | Omega | 1 | OmnicronConspiracy | 1 | ||
| OneStepBeyond | 1 | Onslaught | 1 | OnTheBallWorldCupEdition | 1 | ||
| OoopsUp | 1 | OperationHarrier | 1 | OperationNeptune | 1 | ||
| OperationStealth | 1 | OperationThunderbolt | 1 | OperationWolf | 1 | ||
| OperationWolfB | 1 | OrientalGames | 1 | Ork | 1 | ||
| Oscar | 1 | Oswald | 1 | Othello | 1 | ||
| Outlands | 1 | OutRun | 1 | OutRunB | 1 | ||
| OutrunEuropa | 1 | OutToLunch | 1 | Outzone | 1 | ||
| Overdrive | 1 | OverdriveB | 1 | Overkill | 1 | ||
| Overlander | 1 | OverTheNet | 1 | Starblaze | 1 | ||
| SteveDavisWorldSnooker | 1 |