Game System
- Ophidian4
- Ophidian 23604
- Orcs vs Dwarves4
- Oriental Heroes4
- Overworld4
- PALLADIUM Game System4
- Palabra4
- Palladium - Beyond the Supernatural4
- Palladium Fantasy RPG4
- Pandemic Survival4
- Pandemic: Reign of Cthulhu4
- Paper Tales4
- Parsely4
- Petrichor4
- Phoenae4
- Pirate's Cove & Jamica4
- Pitch Car4
- PitchCar4
- Pizarro & Co.4
- PlayThings System4