To determine the physical and magical laws of the D&D world, we needed to take a step back and imagine the entire cosmology. Where does magic come from? What about the other sources of power that we wanted to clarify in the game? These discussions led to a re-imagining of the D&D cosmology...
The End of the Great Wheel
The cosmology that has defined the planes of the D&D multiverse for thirty years is a good example of symmetry that ultimately creates more problems than it solves. Not only is there a plane for every alignment, there's a plane between each alignment--seventeen Outer Planes that are supposed to reflect the characteristics of fine shades of alignment. There's not only a plane for each of the four classic elements, there's a Positive Energy Plane, a Negative Energy Plane, and a plane where each other plane meets--an unfortunate circumstance that has resulted in creatures such as ooze mephits.
The planes were there, so we had to invent creatures to fill them. Worse than the needless symmetry of it all, though, is the fact that many of those planes are virtually impossible to adventure in. Traversing a plane that's supposed to be an infinite three-dimensional space completely filled with elemental fire takes a lot of magical protection and fundamentally just doesn't sound fun. How do you reconcile that with the idea of the City of Brass, legendary home of the efreet? Why is there air in that city?
So our goals in defining a new cosmology were pretty straightforward.
- Don't bow to needless symmetry!
- Make the planes fun for adventure!