Basic Psionics Handbook doesn't really introduce the concept of planes for a BX audience that's gamed most of their lives without them. I had originally intended to include an plane-related appendix, but it because so big it was going to end up being as much info as the entirety of the psionics book. That led me to working on a supplement I'm tentatively titling PX2: Basic Atlas of the Planes. It's really going to take me some time to finish this up (another year or so probably). So in the meantime, I've put together a Planar Primer that I hope suffices in the meantime. It includes an introduction to the planes of existence, an overview of the planar cosmology, a schematic of planar interaction, an introdution to travel & encounters on the Astral and Ethereal Planes, and information on plane-related magic.
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