Structure of the Multiverse

The multiverse consists of separate universes known as Reality Spheres, also called Prime Domains. Each is a self-contained cosmic system with its own physical universe and associated planar structure.

Within Eldareth's Reality Sphere are stars, planets, and galaxies, along with the Prime Material Plane, its Echo Planes, the four Elemental Planes, the Energy Planes, the Transitive Planes, the Outer Planes, and a number of less conventional realms that fall outside these categories.

Reality Spheres are separated from one another by Driftspace.

Reality Spheres

Each Reality Sphere is a distinct universe whose planes and physical cosmos belong to that sphere alone. Planes do not naturally extend from one Reality Sphere into another.

Travel from the Material Plane to another plane within the same sphere therefore remains within a single Reality Sphere. Reaching another Reality Sphere requires leaving that cosmic system entirely and crossing Driftspace.

The structure of other Reality Spheres is not necessarily identical to that known in Eldareth. Their planes, cosmological arrangements, and relationships may differ considerably.

Fringe Realms

Not every realm within a Reality Sphere fits neatly into the conventional planar categories.

Such places are often grouped loosely under the term Fringe Realms. The name describes their unusual cosmological position rather than a single shared location or origin.

Val'Syra is one such realm within Eldareth's Reality Sphere. The Far Realm is another, existing along the distorted outer fringes of Eldareth's planar structure.

Other anomalous realms and demiplanes may also fall within this broad classification, depending on their nature and relationship to the wider cosmology.

The Far Realm

The Far Realm lies at the outer fringes of Eldareth's Reality Sphere, beyond the ordered arrangement of its better understood planes.

It remains part of Eldareth's cosmology rather than Driftspace, but its environments do not always conform to the physical or magical principles familiar elsewhere in the sphere.

The Far Realm is inhabited and possesses its own landscapes, ecosystems, and civilizations. Its unusual conditions can affect perception, matter, and magic in ways that remain poorly understood by most planar scholars.

Travel to it does not form part of the ordinary Astral or Ethereal transit networks.

Driftspace

Driftspace is the expanse separating one Reality Sphere from another.

It does not belong to any single universe. Travelers entering it leave the normal planar structure of their Reality Sphere and pass into a region where ordinary methods of planar navigation are no longer reliable.

Driftspace contains unstable magical currents, fragments of collapsed realities, ruined vessels, and remnants of routes once used by civilizations capable of traveling between universes.

The Koryphai and Naerids were among the peoples known to have navigated Driftspace successfully. Surviving evidence indicates that reliable travel depended upon established routes, navigational systems, and vessels specifically designed to endure the journey.

Forms of Travel

Travel through the known cosmos is generally divided into three broad forms: spacefaring, planesfaring, and multiversal travel.

Spacefaring

Spacefaring is travel through the physical space of a single Reality Sphere.

Advanced vessels can cross the distances between worlds and stellar systems using arcane propulsion and other specialized technologies. Navigation may rely on stellar phenomena, magical currents, and charts anchored to known celestial or magical reference points.

Galarium can be incorporated into some forms of advanced propulsion and navigation, serving as a medium through which magical energy is stored, conducted, and regulated. No civilization currently known within Eldareth has developed a Galarium-based vessel capable of crossing a planar boundary.

A spacefaring vessel remains within the physical cosmos of its Reality Sphere unless it possesses some separate means of planar or multiversal travel.

Planesfaring

Planesfaring is travel between the planes and realms contained within a single Reality Sphere.

Spells, stable portals, and established planar routes provide the most familiar means of crossing these boundaries. More advanced civilizations have also constructed vessels capable of planar travel.

Travel from Eldareth to the Astral Plane, an Elemental Plane, an Outer Plane, or another accessible realm within the same Reality Sphere is therefore planesfaring rather than multiversal travel.

The difficulty of such a journey depends on the destination and the relationships between the planes involved. Some are connected through established transitive routes, while others require direct planar magic or specially constructed crossings.

Multiversal Travel

Multiversal travel is movement from one Reality Sphere to another through Driftspace.

Known methods have required ancient beacons, navigational matrices, established routes, and vessels capable of functioning beyond the planar structure of an ordinary Reality Sphere.

Without these systems, navigation becomes extremely unreliable. A vessel may lose its route, fail to locate another Reality Sphere, or become unable to find its way back to the universe it left.

The Koryphai and Naerids are the only civilizations known in Eldareth to have practiced multiversal travel on a large scale.

The Koryphai and Pattern Lattices

The Koryphai developed one of the earliest known systems for navigating Driftspace.

Their Pattern Lattices established stable routes and reference points between Reality Spheres, allowing vessels to navigate regions that would otherwise be extremely difficult to cross.

These routes once formed an extensive network. Many surviving sections are now dormant, damaged, inaccessible, or entirely lost.

The knowledge required to construct new Pattern Lattices is no longer known in Eldareth.

The Naerids

The Naerids traveled between Reality Spheres after the height of Koryphai civilization.

They made use of surviving portions of the Pattern Lattices alongside navigational knowledge associated with Athrakan, the Axis Shard.

Both civilizations also used enormous vessels known as vault-arks. These ships served as transports, shelters, and navigational platforms capable of crossing stellar distances, planar boundaries, and the expanses between Reality Spheres.

How much Naerid multiversal travel depended upon Koryphai technology remains uncertain. Surviving evidence shows that they used portions of the older network, but does not establish how much of its workings they understood or reproduced independently.

Knowledge in Eldareth

Most people in Eldareth have little knowledge of the larger multiverse.

The existence of other planes is widely accepted among scholars, priests, and mages, but far fewer understand that these planes belong to a single Reality Sphere or that other self-contained universes exist beyond it.

Knowledge of Driftspace is rarer still. References to Pattern Lattices, vault-arks, and multiversal travel survive primarily in ancient ruins, fragmented records, and sources associated with civilizations such as the Koryphai and Naerids.

Even scholars specializing in planar travel may therefore know little about travel between Reality Spheres.

Hazards of Driftspace

Driftspace remains dangerous even along routes once used by the Koryphai or Naerids.

Unstable magical currents can distort navigation or force vessels away from established routes. Fragments of collapsed realities, ruined ships, and other debris also persist between Reality Spheres, sometimes gathering around the remains of ancient crossings.

Harvester ships have been reported along remote routes and near regions rich in magical or biological material. They are described as immense hive-vessels that collect resources, specimens, and other material of interest, though their origin and wider purpose remain poorly understood.

Ancient routes present dangers of their own. Pattern Lattices may be damaged, dormant, or incomplete, and a route that once functioned reliably may no longer lead where surviving records claim.

The most common danger remains becoming lost. Without a functioning beacon, navigation matrix, or established route, there may be no reliable means of locating another Reality Sphere or returning to the one a traveler left.