Ethereal Plane

Tamlin felt a hand on him, felt his body shimmer into mist. The screams and shouts sounded far off. The walls around him appeared to be only gray shadows. Rivalen and Brennus stood beside him.
“The ethereal plane,” Rivalen said. “The dragon’s breath cannot affect us here.”

— Paul S. Kemp, Shadowstorm

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.

d8	Plane	Color of Curtain
1	Material Plane	Bright turquoise
2	Shadowfell	Dark gray
3	Feywild	Opalescent white
4	Plane of Air	Pale blue
5	Plane of Earth	Reddish-brown
6	Plane of Fire	Orange
7	Plane of Water	Green
8	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 1d10 × 10 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. Travelers with a passive Wisdom (Perception) score of 15 or more receive 1d4 rounds 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. Roll a d20 and consult the Ether Cyclone table to determine the effect on all creatures in the vicinity.

d20	Effect
1-12	Extended journey
13-19	Blown to the Border Ethereal of a random plane (roll on the Ethereal Curtains table)
20	Hurled into the Astral Plane

The most common effect of an ether cyclone is to extend the duration of a journey. Each character in a group traveling together must make a DC 15 Charisma saving throw. If at least half the group succeeds, travel is delayed by 1d10 hours. Otherwise, the journey’s travel time is doubled. 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.

Type

Dimensional plane