Swedish publisher Free League continues to champion community content, today releasing a new open game license for its recently launched sci-fi roleplaying game, Coriolis: The Great Dark. This move allows creators to freely publish and sell their own adventures and supplements for the game without paying royalties.

The new license joins a growing ecosystem of similar agreements from the publisher, which already offers open licenses for the fantasy RPG Dragonbane and its core Year Zero Engine rules system. This decision places Free League firmly within a broader industry trend of publishers embracing more open and irrevocable licenses, a movement that gained significant momentum following Wizards of the Coast’s controversial handling of Dungeons & Dragons’ own OGL.
Coriolis: The Great Dark is a science fiction RPG that blends themes of 19th-century expeditions, deep-sea diving, and pulp archaeology. Players take on the roles of Explorers, venturing from the dying Ship City into enigmatic ruins to uncover secrets and artefacts, all while contending with a mysterious plague known as the Blight.
The new third-party license is designed to be straightforward, granting creators a perpetual, non-exclusive, and worldwide right to create and sell compatible material. Crucially, the license is irrevocable, a key feature designed to build creator confidence. This means that while Free League may update the license, creators can always choose to use the version they originally published under.
However, prospective creators should take note of some important limitations within the agreement. The license is currently only for English-language supplements and specifies that creations must be supplements, not standalone games, requiring the Coriolis: The Great Dark core rulebook to be played.
Mechanically, the license is quite specific. While it allows for the addition of new talents, professions, gear, and rules for situations not covered in the core game, it explicitly forbids the creation of new attributes. The text further states that “Free League discourages the adoption of new rules for your Supplement,” signalling a clear preference for content that expands the existing game world rather than fundamentally altering its mechanics. This could present a challenge for creators hoping to innovate heavily on the core system.
The release is another sign of the tabletop industry’s shifting landscape. Following the D&D OGL incident, in which Wizards of the Coast attempted to de-authorise a license used for over two decades, many publishers have moved to create their own, more robust open systems. Companies like Kobold Press moved to announce new open RPG systems to reassure their communities and provide stable platforms for creators.
Free League’s approach with its trio of licenses – for the Year Zero Engine, Dragonbane, and now Coriolis: The Great Dark – demonstrates a clear strategy to foster and support a vibrant community of independent creators around its flagship titles.
The full license text and the official logo for use on third-party products are now available on the Free League Publishing website.
Quick Links
- Buy: Coriolis: The Great Dark
- License: Free to Read