Mapping the Multiverse: Decoding the Radiant Citadel Chart

Ever since the Radiant Citadel floated into the Ethereal Plane, GMs have been trying to figure out exactly where these new civilizations fit into the grander scheme of the multiverse. We have finally seen a comprehensive chart mapping these parallel cultures and their Earth-inspired motifs across D&D history. It is a tool that does more than just fill space; it provides a much-needed bridge between the new settings and the legacy worlds we have been running since the days of THAC0.

From a crunch perspective, this chart is a godsend for anyone running a high-level planar campaign. Instead of hand-waving the distance between the Akosuz and the Great Wheel, GMs can now use these cultural parallels to determine trade routes or even logical adventure hooks that feel earned rather than arbitrary. It helps standardize the mechanical expectations of a party traveling from a high-magic urban hub to a wilderness-heavy setting by grounding them in recognizable cultural archetypes.

The fluff here is where the setting actually gains its weight. By explicitly linking these civilizations to their real-world inspirations and their counterparts in settings like Greyhawk or Kara-Tur, the multiverse feels less like a collection of isolated bubbles and more like a coherent ecosystem. It provides the lore-heavy GMs with the connective tissue needed to explain why a cleric from San Citlán might find common ground with a paladin from the Sword Coast. This isn't just corporate flavor text; it is a structural guide for cross-setting continuity.

At the table, this reduces the friction of introducing brand-new concepts to your players. We have all faced that blank stare during a session zero when describing a setting that is too alien. This chart allows a GM to say, This is the vibe, and here is how it relates to what your character already knows. It is about reducing the cognitive load on the players while increasing the richness of the world-building. It makes the multiverse feel lived-in rather than just a series of combat encounters.