Description
Ethereal Entities: Denizens of the Unseen Realm by Mordenkainen is a slim hardback book with a leather cover dyed a deep, midnight blue. Its title and author’s name are embossed in silver script along the spine and front cover, and the corners of the book are adorned with small, silver filigree resembling ethereal wisps. Its pages are filled with neatly-written text and beautifully detailed illustrations.
The book is a treatise on the Ethereal Plane and the creatures that dwell within or visit it.
Contents
The Ethereal Plane
The Ethereal Plane is a misty, fog-bound dimension. Its “shores,” called the Border Ethereal, overlap the Material Plane and the Inner Planes, so that every location on those planes has a corresponding location on the Ethereal Plane. Visibility in the Border Ethereal is limited to 60 feet The plane’s depths comprise a region of swirling mist and fog called the Deep Ethereal where visibility is limited to 30 feet. Characters can use the etherealness spell to enter the Border Ethereal. The plane shift spell allows transport to the Border Ethereal or the Deep Ethereal, but unless the intended destination is a specific location or a teleportation circle, the point of arrival could be anywhere on the plane.
Border Ethereal
From the Border Ethereal, a traveler can see into whatever plane it overlaps, but that plane appears muted and indistinct, its colors blurring into each other and its edges turning fuzzy. Ethereal denizens watch the plane as though peering through distorted and frosted glass, and can’t see anything beyond 30 feet into the other plane. Conversely, the Ethereal Plane is usually invisible to those on the overlapped planes, except with the aid of magic.
Normally, creatures in the Border Ethereal can’t attack creatures on the overlapped plane, and vice versa. A traveler on the Ethereal Plane is invisible and utterly silent to someone on the overlapped plane, and solid objects on the overlapped plane don’t hamper the movement of a creature in the Border Ethereal. The exceptions are certain magical effects (including anything made of magical force) and living beings. This makes the Ethereal Plane ideal for reconnaissance, spying on opponents, and moving around without being detected. The Ethereal Plane also disobeys the laws of gravity; a creature there can move up and down as easily as walking.
Deep Ethereal
To reach the Deep Ethereal, one needs a plane shift spell or arrive by means of a gate spell or magical portal. Visitors to the Deep Ethereal are engulfed by roiling mist. Scattered throughout the plane are curtains of vaporous color, and passing through a curtain leads a traveler to a region of the Border Ethereal connected to a specific Inner Plane, the Material Plane, the Feywild, or the Shadowfell. The color of the curtain indicates the plane whose Border Ethereal the curtain conceals; see the Ethereal Curtains table below.
| Plane | Color of Curtain |
|---|---|
| Material Plane | Bright turquoise |
| Shadowfell | Dusky grey |
| Feywild | Opalescent white |
| Plane of Air | Pale blue |
| Plane of Earth | Reddish brown |
| Plane of Fire | Orange |
| Plane of Water | Green |
| Elemental Chaos | Swirling mix of colors |
| Traveling through the Deep Ethereal to journey from one plane to another is unlike physical travel. Distance is meaningless, so although travelers feel as if they can move by a simple act of will, it’s impossible to measure speed and hard to track the passage of time. A trip between planes through the Deep Ethereal takes a random amount of time (up to 100 hours), regardless of the origin and destination. In combat, however, creatures are considered to move at their normal speeds. |
Ether Cyclones
An ether cyclone is a serpentine column that spins through the plane. The cyclone appears abruptly, distorting and uprooting ethereal forms in its path and carrying the debris for leagues. Wary travelers can detect a sign of warning: a deep hum in the ethereal matter. Travelers who can’t reach a curtain or portal leading elsewhere suffer the cyclone’s effect. The most common effect of an ether cyclone is to extend the duration of a journey, sometimes doubling it. Less often, a group is blown into the Border Ethereal of a random plane. Rarely, the cyclone tears a hole in the fabric of the plane and hurls the party into the Astral Plane.
Ethereal Plane Encounters
Most encounters in the Border Ethereal are with creatures on the Material Plane whose senses or abilities extend into the Ethereal Plane (phase spiders, for example). Ghosts also move freely between the Ethereal and Material Planes.
In the Deep Ethereal, most encounters are with other travelers, particularly ones from the Inner Planes (such as elementals, genies, and salamanders), as well as the occasional celestial, fiend, or fey.
Bestiary of the Ethereal Plane
Etherborn: Natives of the Deep Ethereal
Containing information about creatures said to dwell solely in the Deep Ethereal.
Mistfiends
Some scholars and sages believe a mistfiend is the incomplete manifestation of a demon on the Material Plane. Others conjecture it is a representation of chaos unleashed by the denizens of the Abyss. Whatever the true nature of its origin, a mistfiend is a creature wholly chaotic and evil. When encountered on the Material Plane it is most often in areas of consecrated ground such as graveyards, temples, and holy sites. In their native environment, mistfiends are found haunting the most putrid and disgusting of the Abyssal planes. Those planes covered with oozes, mires, fens, and swamps are favored by these creatures. Mistfiends have voracious appetites and always seem to be on the hunt. They are carnivorous creatures devouring just about anything they came across.
Once a mistfiend slays its prey, it moves over the body and rapidly digests it, draining blood and body fluids, and leaving nothing more than a dried husk.
A mistfiend’s semi-solid body is composed of a strange, sickly green and ever-shifting mist. It can change its color to a semi-translucent whitish smoke, thereby blending in and hiding in areas of normal fog and mist. When hiding in this way, a mistfiend seeks to quickly close ground with its target and attack from ambush, unleashing its psychic crush and enervating attacks at the closest and strongest opponents.
Mistfiends are often found in the employ of clerics dedicated to the demonic lords (particularly Tsathogga and Jubilex), serving as temple guards or assassins.
Ethershades
Ethershades are predatory entities that haunt the depths of the Deep Ethereal, their forms resembling tattered shadows wrapped in wisps of gray mist. They are believed to be the degraded remnants of souls that became lost in the ethereal currents—travelers who wandered too long without anchor or purpose, their identities slowly dissolving until nothing remained but hunger and malice.
An ethershade appears as a vaguely humanoid silhouette, its edges constantly fraying and reforming as though caught in an invisible wind. Where its face should be, there is only a darker void, and its touch brings a numbing cold that seeps into both body and spirit. Unlike ghosts, which retain some echo of their former selves, ethershades are wholly consumed by their predatory nature.
These creatures lurk in the foggiest reaches of the Deep Ethereal, drawn to the presence of living souls. They can sense when a creature becomes ethereal through magic, and they track such travelers with patient, inexorable hunger. An ethershade feeds by wrapping itself around its victim like a shroud, draining the warmth and vitality from living tissue while simultaneously leeching away memories and identity.
Victims who survive an ethershade attack often report a profound sense of disconnection afterward—forgetting the names of loved ones, losing cherished memories, or feeling as though parts of themselves have simply vanished. Those who fall prey to multiple attacks risk the same fate as the ethershade itself: becoming lost in the mists, their soul slowly unraveling until nothing remains but another hungry shadow.
Ethershades rarely venture into the Border Ethereal, as the proximity to the Material Plane seems to cause them discomfort. However, particularly bold or desperate specimens have been known to phase briefly into reality when pursuing wounded prey. Travelers who encounter ethershades in the Deep Ethereal are advised to seek the nearest color curtain immediately, as these creatures are relentless once they’ve caught a victim’s scent.
Some scholars theorize that ethershades were once mortal spellcasters who attempted to explore the Ethereal Plane without proper preparation or guidance, becoming stranded when their magic failed. Others believe they are a natural hazard of the plane itself—manifestations of the entropy that slowly erodes all things that linger too long in the mists. Whatever their origin, ethershades serve as a grim warning: the Ethereal Plane is not meant for prolonged habitation by mortal souls.
Shimmerlings
Shimmerlings are curious creatures native to the Border Ethereal, manifesting as dancing motes of opalescent light that drift and swirl through the misty veil. Unlike the predatory entities that haunt the Deep Ethereal, shimmerlings appear benign—even playful—drawn to sources of strong emotion, magical energy, or unusual activity on either side of the planar boundary.
A shimmerling resembles a cluster of soap bubbles infused with soft, constantly shifting colors—pale blues, gentle purples, warm golds, and cool silvers that ripple across its translucent form. When multiple shimmerlings gather, they create mesmerizing displays of light and movement, spiraling around each other in elaborate patterns. They range in size from that of a firefly to that of a lantern, and their luminescence provides welcome illumination in the perpetual twilight of the Border Ethereal.
These creatures seem to possess a rudimentary intelligence and an insatiable curiosity about the Material Plane. Travelers report shimmerlings following them through the Border Ethereal, clustering around areas where magic is being cast on the Material Plane, or gathering at sites of intense emotional significance—battlefields, places of worship, locations where great joys or tragedies occurred. Some ethereal explorers claim that shimmerlings are drawn to the “echoes” that strong emotions leave on the fabric of reality.
While generally harmless, shimmerlings can become problematic in large numbers. A swarm of curious shimmerlings will investigate anything new or interesting, and their touch causes a tingling sensation—uncomfortable but not painful. Prolonged contact with many shimmerlings, however, can cause disorientation and mild hallucinations as their ethereal energies interfere with mortal perception. More than one traveler has become hopelessly lost in the Border Ethereal after being “guided” off course by an enthusiastic cluster of shimmerlings.
The creatures seem capable of communicating through patterns of light and color, flashing in sequences that some scholars believe represent a primitive language. A few ethereal travelers claim to have established rapport with shimmerlings, using them as guides to navigate the Border Ethereal or as early warning signals when other, more dangerous entities approach.
One peculiar trait of shimmerlings is their reaction to ghosts and other ethereal undead: they dim their lights and flee from such creatures, as though frightened or repulsed. This behavior has led some researchers to theorize that shimmerlings might be fragments of positive planar energy—manifestations of life and vitality that naturally recoil from the presence of undeath.
Shimmerlings have no known method of reproduction and do not seem to age or die. They simply exist, drifting through the Border Ethereal in their eternal dance, drawn to whatever catches their boundless curiosity.
Phantomfolk: Travelers from the Border Ethereal
Containing information about incorporeal creatures that dwell in the Border Ethereal and often cross into the Material Plane.
Ghosts
Ghosts arise when living creatures die in a state of extreme emotion or having left an important task undone. These incorporeal spirits haunt locations that are meaningful to them, lingering until their business is complete or they’re put to rest.
Ghosts typically appear as semitransparent versions of the creatures they were in life, though some bear evidence of the wounds that killed them or have nightmarish distortions to their forms. Many have extreme reactions to actions, objects, or individuals that remind them of emotionally charged aspects of their lives. Particularly desperate or vengeful ghosts might possess the living to fulfill their ends.
Phantom Warriors
A phantom warrior is the spectral remnant of a willful soldier or knight who perished on the battlefield or died performing its sworn duty. It appears like a translucent version of its living self.
Task Driven. Although one is often mistaken for a ghost, a phantom warrior isn’t bound by a yearning to complete some unresolved goal. It can choose to end its undead existence at any time. Its spirit lingers willingly, either out of loyalty to its former master or because it believes it must perform a task to satisfy its honor or sense of duty. For example, a guard who dies defending a wall might return as a phantom warrior and continue guarding the wall, then disappear forever once a new guard assumes its post or the wall is destroyed. The period between the time it died and the time it rises as a phantom warrior is usually 24 hours.
Faded Memories. A phantom warrior retains the alignment and personality it had before it died, and it remembers how it died. Memories of its life from shortly before it died are hazy, and older memories are forgotten. A phantom warrior can usually remember the last few days of its life; everything that happened before that is an impenetrable fog.
Forceful Presence. Although they are incorporeal, phantom warriors can harness the energy around them to deflect incoming attacks and strike with great force. An invisible sheath of energy surrounds a phantom warrior’s ghostly armor, shields, and weapons, which become as hard as steel yet don’t impede the warrior’s ability to move through walls and other solid objects.
Undead Nature. A phantom warrior doesn’t require air, food, drink, or sleep.
Veil-Walkers: Visitors to the Ethereal
Containing information about physical creatures that can cross into the Ethereal Plane.
Night Hags: Matrons of Malevolence
Sly and subversive, night hags are the epitome of wickedness. They represent all that is evil and cruel in the world and want nothing more than to see the virtuous turn to villainy: love turned into obsession, kindness turned to hate, devotion to disregard, and generosity to selfishness.
Once, night hags were creatures of the Feywild, a realm of enchantment and beauty. However, their foulness saw them exiled to the bleak realm of Hades long ago, where they degenerated into fiends. The foul taint of Hades twisted their once-fey nature, and the night hags have long since spread their malevolence across the Lower Planes.
Though night hags resemble withered crones, there is nothing mortal about them. Their withered faces are framed by long, frayed hair and curled ram’s horns; horrid moles and warts dot their blotchy pale-blue skin; and their long, skinny fingers are tipped by claws that can slice open flesh with a touch.
All hags possess magical powers, including the ability to alter their forms or curse their foes. A hag also bears some resistance to magic and mortal weapons alike, though the touch of silver wounds her like any other.
Arrogant to a fault, hags believe themselves to be the most cunning of creatures—and very often are. They are open to dealing with mortals, and will always keep their word—but a bargain with a hag is always dangerous. Hags enjoy watching mortals bring about their own downfall through these bargains, which often involve compromising their principles or giving up something dear.
A night hag’s ultimate prize, however, is the soul of a corrupted mortal. While her victim sleeps, the night hag passes into the Ethereal Plane through the aid of her twisted onyx heartstone—an artifact that allows her to become Ethereal at the speed of thought. There, she invades her victim’s very dreams, filling their head with doubts and fears in the hope of tricking it into performing evil acts in the waking world.
Night after night, she continues her visitations until the victim finally expires in its sleep—at which point she traps its corrupted soul in her soul bag as a dark trophy of her success. The blacker the stains upon the soul, the greater the night hag’s bounty.
Like all hags, night hags propagate by snatching and devouring human infants. A week later, the hag gives birth to a daughter who appears human until her thirteenth birthday—at which point the child transforms into the spitting image of her hag mother.
Some hags raise the daughters they spawn, creating covens that magnify their power. The members of a coven gain a slew of unnatural abilities, including the power to control the elements and—once each day—to dispel foreign magic in the vicinity of their lairs. As is true for all hag magic, however, such power comes at a price—for a wound suffered by a single hag in a coven is suffered by all.
To combat their inherently selfish natures, the hags in a coven must enter into a written contract with the others, signed by each hag’s true name. The hags of a coven guard their contract jealously, often sealing it within the heart of their lair, ever-careful to keep their names from falling into enemy hands.
Nightmares
Nightmares resemble horses with flaming manes, burning hooves, and smoldering eyes. They terrorize weaker creatures and often ally with denizens of the Lower Planes in committing evil acts. These supernatural horses can innately travel between the Ethereal Plane and the Material Plane, and many know the locations of portals to the Lower Planes, the Shadowfell, and other sinister realms.
Nightmares’ speed, resilience, and ability to gallop between planes of existence make them steeds coveted by evildoers.
Phase Spiders
A phase spider possesses the magical ability to phase in and out of the Ethereal Plane. It seems to appear out of nowhere and quickly vanishes after attacking. Its movement on the Ethereal Plane before coming back to the Material Plane makes it seem like it can teleport.
Phase Spider Fangs & Venom
Since most incorporeal undead have an immunity to elemental, natural, and nonmagical weapon damage while on the Material Plane, and phase spiders have developed a natural means to counteract those immunities through the use of their fangs and venom. A spellcaster can deal damage to an incorporeal spirit normally by using a phase spider’s fang as an additional material component to cast their spells, while a martial combatant can deal damage to an incorporeal spirit by coating one weapon or up to three pieces of ammunition with phase spider venom or holy water.