The Planes: Physical Reality

The Material Plane

The Material Plane is the plane of existence that we all live on. It has a single set of natural laws that all existence abides by. In a standard campaign, it typically functions in the same way our universe does, with clusters of galaxies made of billions of stars, some with planetary systems orbiting them. It is, at least theoretically, infinite.

Because it is what we as players (and as characters) are by far most familiar with, the Material Plane serves as the standard by which all other planes tend to be measured. While this can help make the other planes easy to understand, it is important to remember that only the Material Plane itself (and probably a few demiplanes) actually abide by the natural laws it has in place. Viewing the other planes with a strictly material perspective turns them into impossibilities.

The Material Plane is always unaligned, all elements are represented in the natural order and its laws are static. It therefore becomes easy to assume that the Material Plane is a plane of near-perfect balance (though it does have a slight lawful leaning), especially when its laws are the ones we know; however, while this is mostly true, there is one very important and easily over-looked imbalance in the Material Plane. Positive energy is dominant over negative energy. Don't get me wrong, the Material Plane is ALWAYS completely unaligned. Negative energy is able to exist within the Material Plane just as easily as positive energy; it just doesn't exist in anywhere near the same quantity. This is the reason life is abundant in places and undeath doesn't occur naturally.

Also, for every Material Plane there is an "equal but opposite" unaligned plane where negative energy is dominant over positive (the Plane of Shadows). Furthermore, since these planes coexist (overlap completely), they form a sort of "buffer zone" together where both energies are equal (the Ethereal Plane). These imbalances must exist (and must balance out) in order for a Material Plane to exist at all. Otherwise, it would just be another section of the empty void that is the Astral Sea.

Many campaigns only have one Material Plane. Since it is effectively infinite, it would be sufficient to cover all realms of possibility (under one set of natural laws). However, since the Astral Plane is also infinite, many DMs will say that there are an infinite number of Material Planes. Either way can be correct, and it's up to your DM to decide which is true.

As a DM, when considering if your campaign has one or infinite Material Planes, consider one question. How were they formed? If you decide that there is a chance (however miniscule) that rogue energies in the Astral Plane alone can form the necessary imbalance to create a Material Plane, then there would be infinite Material Planes (since the Astral Plane is infinite). However, if you decide that a Material Plane forming on its own is impossible and divine help is required, then in all likelihood there would only be one. Remember, either way can be correct.