Why the Material Plane is Important

Most Dungeons & Dragons one-shots, adventures, and campaigns occur on the Material Plane. Also known as the mortal world, the Material Plane is where low-to-medium-level characters quest, smite down evil warlords, and plot against maniacal archmages. The majority of its population is mortal; they are dwarves and elves, humans and halflings, dragonborn and goblins, orcs and giants. Usually, adventures don’t leave the mortal world until higher levels, when conflicts between planar creatures like devils and celestials fling important characters to the Nine Hells, Mount Celestia, the Abyss, or other planes of existence. Even then, the plot might center around the Material Plane.

This begs the question: why is the Material Plane important?

A Place of Neutral Perfection

It’s often stated that the Material Plane is where the elements and alignments of the multiverse converge.

The Plane of Fire is a realm of raw, fiery energy: flames blaze across the sky and rivers of lava flow into molten seas. Its opposite, the Plane of Water is an unending ocean, peppered with ships lost at sea and thrust into the maelstrom of this elemental body. In the trenches of the Inner Planes is the Plane of Earth, a limitless cavern with a crystalline sky and boulders that tumble perpetually across the land. High above is the Plane of Air, a cloudy realm littered with flying fortresses and hazy winds. Layered outside these areas of pure elemental energy are the various planes of alignment. Realms like the Abyss and the Hells harbor the forces of evil, Celestia protects the creatures of good, Mechanus tinkers with the tools of absolute law, and Limbo manipulates all that is chaotic.

All of these planes of existence surround the world where mortals live: the Material Plane. They coalesce and form a space inhabitable by creatures not bound to a single facet of the universe. In the mortal world, efreeti can thrive, aboleths can plot for eternity, devils can tempt dull mortals, angels can attempt to lighten dark hearts, and creatures such as dwarves can live amongst them all. No matter the origins of a creature, it can survive in the mortal world with little to no issues. Compare this with a water elemental trying to move across the Plane of Fire, a devil attempting to connive their way into Celestia, or a slaadi sneaking past the sleepless modrons of Mechanus. All of those scenarios are possible, of course, but they are unlikely and absolutely maddening!

This is one reason why the Material Plane is important: all of the creatures we know and love in D&D can coexist there, even though this often leads to deadly encounters and terrifying schemes. Without the Material Plane, D&D adventures would have no middle ground for interesting entities to meet.

The Material Plane is a place of neutral perfection that’s necessary for almost all D&D games because it’s where all the entities of the multiverse converse, combat, and create. However, this is far from the only reason it’s vital to our D&D worlds…

The Prime Material Plane

In the most prominent cosmology in D&D, the Great Wheel, the Material Plane is usually referred to as the Prime Material Plane.

The Prime collects every single D&D world in existence, from the published setting of Toril and the slightly variant replicas of Toril used in thousands of D&D campaigns to every other world not split out into a separate cosmology. Altogether, these worlds are simply referred to as the Prime; they are the nexus for all other planes. They exist separate from each other in glass-like domes, unique.

Usually, there are no other ways to travel between planes of existence without passing through the Prime in some manner. For example, the Astral and Ethereal are not connected to each other. Likewise, the Inner and Outer Planes usually require passing through the Prime to reach each other. Thusly, in key planar locales such as Sigil, the Prime is used as the focal point for all planar travel. When talking about the Plane of Fire in relation to the Abyss, creatures direct from the Prime, not from one location or the other. Again, this is only in the standard Great Wheel cosmology — it might be completely different in your own world, as it is in mine.

Nonetheless, the Prime is a necessary conduit between the many worlds of D&D in a majority of campaign settings.

The early cosmology of my world, Eldar.

Souls for Harvesting

Malicious beings like devils need the mortal world to thrive and exist because it provides the fuel for infernal hordes, but that’s not the only type of harvesting that occurs in the multiverse.

Fleshy bodies on the mortal world are filled with rich souls. These souls contain the personality and consciousness of the body, defining what makes one human or dwarf different from another. Without them, all creatures would simply look different but act similarly, like automatons. This is in direct conflict with planar creatures like devils. Mostly, they’re seen to be embodiments of a certain belief or ideal that then takes shape. A barbed devil has a soul that appears to be a barbed devil, but that appearance is malleable while, in many cases, the soul itself is defined. While this is how souls are viewed by many, others across the multiverse see these souls as opportunities.

Devils, in particular, covet souls greatly. They are used as currency in the Hells. Powerful devils wager souls on risky wagers, pay their infernal masters with souls, and use souls to bolster their ranks. Every soul promised to the Hells is another member in the massive society of devils.

Souls are also harvested from the mortal world for other planes of existence. In many worlds, the souls of a pious believer of a certain god travel to that deity when they die and become one with them, bolstering the god’s strength. In other worlds, souls travel to a particular afterlife to live the rest of eternity in the multiverse. Some souls promised to the Hells swoop there and become lemures. Other souls destined for the war-torn fields of Asgard join the deathless combatants there.

When a mortal dies, their soul is harvested for a particular destination. Whether its the Hells or an idyllic plane like Mount Celestia, souls departing the Material Plane and joining the limitless planes of existence is a natural part of many D&D settings. The Material Plane is the field in which the soul is harvested; it serves as a home where the soul can grow and flourish.

This provides a plethora of plot hooks for adventures. Here are a few.

• The soul of the party's patron is bound to a prominent devil. The patron needs them to wrestle it free from the devil.
• Thousands of souls arrive at the wrong destination in the afterlife, leading to a mass haunting of a particular plane like Mechanus or Limbo. If the souls are not brought to the correct plane of existence, there might be extreme fallout.
• The god whose domain is the speedy and safe travel of souls from the Material Plane to the afterlife is killed, leading to the pollution of souls in the Material Plane. Various factions across the multiverse break into it to compete for the free souls.

Art from Baldur's Gate: Descent Into Avernus.

Material Plane Examples

Across the editions of D&D, there are multiple prominent examples of the Material Plane. Here is a brief selection of them.

• Toril. Often called the Forgotten Realms, Toril is the primary setting of D&D. It's high fantasy and home to a plethora of famous heroes and adventures.
• Eberron. The folk of this Material Plane are sectioned off from the rest of the regular D&D multiverse. As a result, the entities here have evolved separately from the common canon.
• Athas. The gods are absent in the Material Plane attached to the Dark Sun campaign setting. Many species are extinct and the world is steadily dying.
• Oerth. Greyhawk and all its adventures originate on the Material Plane of Oerth, Gary Gygax's own campaign setting. 
• Aebrynis. The homeworld of the Birthright campaign setting. This Material Plane revolves around the bloodlines of key adventurers across the land and the growth of their lineages.
• Krynn. The epic saga Dragonlance occurs in this Material Plane that pits good versus evil in a clear way.

Making Your World’s Material Plane Unique

The Material Plane is important in almost every D&D setting, yes, but how is it important and unique in your setting?

Start by meandering over special traits of the Material Plane common across the vast worlds of D&D. For example, when a devil dies on the Material Plane, it’s not truly dead. Instead, its being is transferred back to the Hells where it must be killed; to die on the Material Plane is a major inconvenience for a devil, but not a total defeat. Here are a few suggestions to add some flavor to your Material Plane.

• Death is unique to the Material Plane. Creatures cannot die while on other planes of existence. When they would be killed, they are thrust back to the mortal world.
• The only realm where creatures can age is the Material Plane. Elsewhere, they are timeless.
• The other planes of existence are interwoven with the Material Plane. For example, the Hells are actually on the planet, as are the Heavens and the forests of the Feywild.
• The gods live and breathe on the Material Plane.
• Spells of neutrality have greater effect on the Material Plane.
• There is only one Material Plane, no others. This is similar to Eberron’s cosmology, wherein the world of Eberron and all its planes of existence appear separately from other Material Planes (Toril, Athas, Oerth, etc).

Lessons Learned

The Material Plane is vital to our D&D adventures. Remember what we cemented about it.

• The Material Plane is a place of neutral perfection. All the elements and alignments of the multiverse converge in it, allowing creatures of all origins to live and thrive there. This makes it the perfect ground for adventure!
• The combination of all the Material Planes across the multiverse is called the Prime Material Plane or the Prime. It serves as a conduit between all the planes of existence, a nexus of sorts.
• The Material Plane is a grand field where the souls of mortals can grow and flourish. Eventually, they are harvested when mortals die and swept to one of the planes of existence.
• It’s easy to spice up your Material Plane. Don’t be afraid to break free from the basic and add awesome elements to it.

Related Articles

• Don’t Be Afraid to Change Your D&D World
• Build With, Not Without, 5e’s Books
• Tenets of D&D Settings

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