Magnus Codex is a wiki-based resource offering tools and reference materials for role-playing games. Its site brings together dedicated sections for La Couleur des Roses, À Fleur de Flingues, and Les Fils du Sort, with practical features designed to support game preparation and play. These include automatic character sheets for all three games, a town-management sheet for La Couleur des Roses, and a non-player character manager for Les Fils du Sort.

Players and game masters can also explore interactive maps of Rosarya and other game settings, helping them navigate the worlds featured in the wiki. Beyond its role-playing resources, Magnus Codex provides access to additional MediaWiki extensions, including Secazame and Typer. The site is organized as a central gateway to its wiki content, game-specific utilities, mapping tools, and extensions.

Its offerings focus on making character creation, setting management, and access to game information more convenient for people using these role-playing resources