As some of you will know, I have been working on making maps for the Inner and Outer Planes of Mystara these last couple of months and posting them on The Piazza.
Paul over at the Mystara Cartography Group on Facebook asked me if I had any reference documents with all the planes listed. That gave me the idea I could do better. What about a full guide to Mystara's Multiverse?
At this point, this is just a draft containing a list of all the planes, dimensions and planar locations that I could find in the published material as well as a few fan created ones.
Check out the first draft here!