[DF] Why is the Prime Material Plane Important?

[Edges]

Originally Posted by roguebfl

I recall it as referring to Alternate Material Planes with Prime being reserved for only he campaign's home plane... that is to say an any given campaign there was only one prime the rest were all alternate.

Actually, he's right. As far back as first ed. D&D, there were conceivably infinite PMPs. An inhabitant of a PMP called their home the PMP and all others alternate PMPs. Each of these had their own Ethereal plane. Thus, travel from one PMP to another was tricky. The PMPs could be widely different in terms of physics, mana-levels, TL, inhabitants, etc. Basically, the infinite worlds game concept for table-top was developed for D&D in the 80s.