Specifically, have an idea to write a dark fantasy story (or rather several), set on the world Carcosa. The complexity is, the world in question was created at different times by Ambrose Bierce, Robert W Chambers, and Geoffrey McKinney. It borrows heavily from HP Lovecraft and the Cthulhu Mythos, but the material from McKinney is based on Dungeons and Dragons (but hardly traditional to that game). So where does this fit? It isn't original. Is it crossover between Cthulhu Mythos and D&D, or would it be most appropriate elsewhere?