Online Tools Online Tools (8/0)
Software & Tools/Online Tools

Operating System Operating System (0/0)
Software & Tools/Operating System

General General (3/1)
Software & Tools/2D Tools/General

Listings:
- OpenCanvas

3D Renderer 3D Renderer (10/1)
Software & Tools/3D Tools/3D Renderer

Listings:
- Octane

RPG / Gaming RPG / Gaming (33/3)
RPG Community/Personal / Gallery/RPG / Gaming

Listings:
- Outer Sanctum of the Trollgod’s Trollhalla
- OSR News
- OSR Today

Old School / Retro Edition Old School / Retro Edition (19/1)
Games/Role Playing Games/By System/Old School / Retro Edition

Listings:
- OSRIC™

Forums Forums (10/1)
RPG Community/Forums

Listings:
- Original D&D Discussions

Atlas Games Atlas Games (4/1)
Games/By Publisher/Atlas Games

Listings:
- Over the Edge

RPG Publisher RPG Publisher (58/2)
Games/By Publisher/RPG Publisher
These are links to the publishers of role-playing games, irrespective of what they publish. Some publishers also have su...

Listings:
- Outland Arts
- OED Games

Dungeons & Dragons Dungeons & Dragons (19/1)
Games/Role Playing Games/By Genre/Fantasy/Fantasy Game Line/Dungeons & Dragons
Dungeons & Dragons (abbreviated as D&Dor DnD) is a fantasy tabletop role-playing game (RPG) originally designed ...

Listings:
- Oriental Adventures 1st Edition

d100 OSR d100 OSR (1/1)
Games/Role Playing Games/By System/Old School / Retro Edition/d100 OSR
Games mostly derived from the Mongoose Publishing RuneQuest SRD.

Listings:
- OpenQuest 2

Open Game License Open Game License (5/0)
Games/Role Playing Games/Open Game License

Sine Nomine Publishing Sine Nomine Publishing (5/1)
Games/By Publisher/Sine Nomine Publishing

Listings:
- Other Dust

Occult Occult (6/0)
Games/Role Playing Games/By Genre/Horror/Occult

Outland Arts Outland Arts (1/0)
Games/By Publisher/Outland Arts

Resellers Resellers (7/1)
RPG Community/Resellers

Listings:
- OneBookShelf

One.Seven Design One.Seven Design (5/0)
Games/By Publisher/One.Seven Design

Other Creative Tools Other Creative Tools (4/0)
Software & Tools/Other Creative Tools
Software applications that are useful for creators.

Old School Renaissance Magazines Old School Renaissance Magazines (4/0)
Games/News/Magazines/Old School Renaissance Magazines
Magazines that cover only or specifically old school renaissance games, but may also cover only specific old school rena...

OSR d20 Variant OSR d20 Variant (1/0)
Games/Role Playing Games/By System/Old School / Retro Edition/d20 OSR/OSR d20 Variant
Games that are based on the d20 rule set but freely mix variant rules from multiple editions.

d6 d6 (5/1)
Games/Role Playing Games/Open Game License/d6
Games derived from an open game license version of a d6 dice pool system.

Listings:
- OpenD6 Fantasy SRD

Original Dungeons & Dragons Original Dungeons & Dragons (5/0)
Games/Role Playing Games/By Genre/Fantasy/Fantasy Game Line/Dungeons & Dragons/Original Dungeons & Dragons

Open Source Open Source (2/0)
Software & Tools/Publisher/Open Source

Espionage Espionage (6/1)
Games/Role Playing Games/By Genre/Espionage

Listings:
- Operators RPG

Origins Origins (3/0)
Awards/Origins

OneBookshelf OneBookshelf (5/0)
RPG Community/Resellers/OneBookshelf
OneBookShelf operates digital download marketplaces focused on several publishing areas like roleplaying games, comic bo...

Online RPG Utilities Online RPG Utilities (3/0)
Software & Tools/Online Tools/Online RPG Utilities