Planes of Eberron
Every child knows the story of the Progenitor Dragons: Siberys, Eberron, and Khyber. In the dawn of time, these three cosmic beings created thirteen planes of existence, each embodying a concept. Their final work was the Material Plane, where all ideas would become manifest: a realm that could know war and peace, life and death, order and chaos. But cruel Khyber sought ultimate dominion over this new reality. She struck Siberys without warning and tore him apart. Eberron wrestled with Khyber and bound the traitor in her coils but could not defeat her. So Eberron became a living prison, a world that would forever contain Khyber’s evil.
Eberron is the heart of the material plane. It is surrounded by the Ring of Siberys, a band of golden dragonshards. Beyond this, twelve moons orbit the world. To date, no creature from Eberron has ever explored the moons. None can say whether they are lifeless rocks or thriving worlds in their own right. Some sages believe that the moons are actually connected to the planes, or that they might even be physical extensions of the planes, but this remains a mystery.
The 13 Planes
The Material Plane is enfolded by thirteen planes of existence. Many of these have aspects of both Outer Planes and Inner Planes. All of them overlap with Eberron in some way, and they influence and are influenced by the Material Plane. The intensity of this influence waxes and wanes; scholars often depict the planes as orbiting Eberron — sometimes coming close, other times far away — though this manner of expression is merely a metaphor for their shifting influence. When another plane’s influence on the Material Plane is especially strong, the plane is said to be coterminous. When its influence is weak, a plane is remote. The state of a plane can be important for performing epic rituals, creating of eldritch machines, or interacting with extraplanar entities. Whether or not a plane is remote or coterminous at a given time depends entirely on the needs of your story.
At certain places in the Material Plane, the barriers between worlds are thin, and some characteristics of another plane can bleed through into the material world. These places are called manifest zones, and the nature of each one is strongly shaped by the plane it connects to. The city of Sharn is located in a manifest zone linked to Syrania that keeps its towers reaching toward the sky and aids flight. Ghosts might linger in a manifest zone associated with Dolurrh, while a manifest zone tied to Lamannia might have wild vegetation and enhance druidic magic. A manifest zone might include a portal that allows free passage from either plane to the other. The descriptions of other planes in this section offer some other possible effects. Most manifest zones have reliable, persistent effects. Some have only weak connections to their planes, and their properties influence the world only when the plane is coterminous.
Fernia: The Sea of Fire
This plane encompasses both the raw elemental power of fire and its versatility: flame used as a weapon, as a force that holds darkness at bay, or as a destroyer and a force for change. Fernia is home to all manner of fire elementals and to celestials and fiends that embrace the same ideals.
To most, Fernia is considered the embodiment of evil in the form of fire, featuring endless pools of magma and flame, dotted with blasted obsidian isles where creatures of fire manifest and make war with one another. Some scholars, however, believe that the plane embodies neither evil nor good, but is merely an elemental force unto itself—representing fire as a destructive force, but also fire as a creative force, one that yields warmth and light and the potential for craft and industry.
When Fernia is coterminous with Eberron, heat waves and drought follow. Volcanoes and magma pools often become portals between the worlds, though inaccessible to most mortals.
Irian: The Eternal Dawn
Irian is the plane of light and hope, the wellspring of positive energy which is the foundation of light, life, and love. The Aereni believe that their Undying draw their power from this plane. Within the plane of Irian, a bright white sun hangs constantly in the sky. Rivers of liquid glass flow from the quartz mountains. White sand deserts and forests of crystals litter the landscape. The regions of Irian reflect the idea of beginnings and of resurgent life: fertile lands untouched by any tool, glittering crystal forests, and thriving homesteads and communities. Angels dwell in a grand city reflecting the first days of a glorious empire. The sun never sets here.
When Irian is coterminous with Eberron, all life is filled with vigor, wounds heal faster, and plants grow vibrantly. Positive energy flows into Eberron from Irian, and the denizens of Irian believe that the simple fact of their existence helps the mortals of the Material Plane. The celestials of Irian are also those most likely to respond to planar ally and similar spells.
Mabar, the Endless Night
Mabar is the darkness that promises to swallow even the brightest day, the hungry shadow that yearns to consume light and life. It is a plane of utter darkness and entropy, antithesis of all life. There, no light shines, its starless night sky persisting for eternity. Mabar is a well of negative energy, fueling decay and empowering the undead, and necromancers from Karrnath and Aerenal have learned to use its power for their own gain. Yugoloths, cruel angels, and creatures of shadow claim Mabar as their home—if they can resist the life-draining darkness.It is the plane of entropy, hunger, and loss, slowly sucking the life from the multiverse. It is the source of negative energy in Eberron. Most undead are animated by the power of Mabar, and the life they drain from mortals flows into the Endless Night.
When Mabar is coterminous with the Material Plane, shadows grow darker and the nights are long and cold. In the deepest blackness, a hapless mortal might accidentally stumble into Mabar itself. Mabar is made up of many fragments, each one representing a different vision of desolation. The fiends of Mabar scheme to steal fragments of other planes and draw them down into their eternal darkness, creating a jumble of broken worlds in varying states of decay.
Risia, the Plane of Ice
The counterpoint to Fernia, Risia embodies winter’s chill and the stoic constancy of the glacier. Risia is the plane of elemental ice and cold constancy. Endless blizzards lash mountains of ice and frigid tundra, and unknown secrets are held in the frozen depths of fathomless arctic seas. It is home to spirits, both fiends and elementals, that embody the ideas of binding ice and deadly cold. Across Risia’s icy expanse, blizzards ceaselessly howl over floes of thick, blue ice, and frost giants carve great fortresses from glaciated mountains. Unprotected visitors perish quickly, but those who adapt to the cold or protect themselves from it can plumb the plane’s frigid depths for ancient secrets.
When Risia is coterminous with Eberron, cold weather becomes more intense and deadly, and magics tied to frost become more powerful.
Thelanis, the Faerie Court
Thelanis, the plane of the fey, is a place where metaphor and narrative holds sway. There, powerful archfey live out their grand tales in realms with the lesser fey, occasionally snatching unwary mortals as players in their grand dramas. Rules that mortals take for granted do not apply in Thelanis, as narrative takes precedence over common sense; if the Story dictates that you arrive precisely at the stroke of midnight, midnight will not come until you arrive. Time and space are likewise not bound by practicality, and mortals that find their way to Thelanis can find the Material Plane flies ahead without them, or even find themselves stepping backward in time upon their return to Eberron.
When Thelanis is coterminous with Eberron, the fey grow more populous and you might accidentally find yourself stepping into a fairy tale.