While this setting uses Dungeons & Dragons 5th Edition as a basis for gameplay, it is not based on the Forgotten Realms setting or general worldbuilding concepts. Instead, it is a highly mixed fantasy setting inspired primarily by cultures that don’t appear as frequently in D&D-type material and by the shared interests of its creators.
Most of the setting information is focused on people and their diverse cultures rather than a broad, overarching cosmology: there are no gods in the D&D sense of distant entities with overwhelming power, but people still believe in deities and mythical figures; there are no officially mapped planes, but things occasionally come and go from places that are still poorly understood. Different nations are not fully unified internally, and certainly not with one another, so the overall world is often referred to by different names by different people. Some origin stories or beliefs may have similarities between nations and cultures, but few can say for sure what is absolute truth due to the murkiness of preserving history.
In the end, the main goal for the setting is to allow even high-level narratives to focus on grounded ideas for characters, nations, and cultures, while maintaining an undefined mysticism and wonder for the larger world.
Want to go straight to making a character? Check Ancestries & Cultures for this setting's replacement for races, and Class Options for suggested ways for your class to fit.