The Ethereal Plane is a misty, fog-bound dimension that is sometimes described as a great ocean. 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. Certain creatures can see into the Border Ethereal, and it is know that certain spells grant that ability as well. Some magical effects also extend from the Material Plane into the Border Ethereal, particularly effects that use force energy.
Visibility in the Border Ethereal is severely limited and the plane’s depths comprise a region of swirling mist and fog called the Deep Ethereal where visibility is even worse.
Denizens of the Ethereal Plane
There are no true inhabitants of the Ethereal Plane. Most encounters are with creatures whose senses or abilities extend into the Ethereal Plane, or travelers from other Planes.
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 a short distance 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.
To reach the Deep Ethereal, one needs powerful spells or arrive by means of a 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.
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.
An ether cyclone is a natural phenomenon that manifests as a serpentine column that spins through the plane. The cyclone appears abruptly, distorting and uprooting ethereal forms in its path and carrying their debris for long distances.
The most common effect of an ether cyclone is to extend the duration of a journey. Less often, a group is blown into the Border Ethereal of a random plane, and rarely the cyclone rears a hole in the fabric of the plane and hurls the travelers into the Astral Plane.