As noted back in Part One, any creature becomes ethereal when it is on the Ethereal Plane. Chapter 5 in the Dungeon Master's Guide includes a detailed a description of the Ethereal Plane; however most difficulties in play arise when creatures on the Material Plane (where most D&D adventures take place) try to interact with creatures on the Ethereal Plane.
Etherealness Basics and Misconceptions
The fundamental thing to remember about etherealness is that an ethereal creature or object is not present on the Material Plane. The Ethereal and the Material Plane are coexistent (see page 150 in the Dungeon Master's Guide), which makes interactions between creatures on the two planes fairly common.
With respect to creatures and objects on the Material Plane, an ethereal creature has many of the properties of invisibility and incorporeality. In fact, the rules often speak of ethereal creatures as invisible and incorporeal. Unfortunately, an ethereal creature is not really invisible (just unseen) and it is not incorporeal at all (though it can do many of the same things that an incorporeal creature can do). This last point is worth repeating: The rules tend to use the terms etherealness and incorporeality interchangeably because it is convenient to do so, but the two are not equivalent. Here's a summary of the abilities and properties an ethereal creature has with respect to objects and creatures on the Material Plane:
Although a creature on the Ethereal can see indistinctly into the Material Plane (see pages 151 and 293 in the Dungeon Master's Guide), creatures on the Material Plane can't see into the Ethereal without some kind of magical aid. A detect invisibility or true seeing spell used on the Material Plane reveals things on the Ethereal.
Because an ethereal creature or object is not actually present on the Material Plane, a creature on the Material Plane cannot make a Spot or Listen check to notice or locate it (because there's nothing at hand to see or hear). Likewise, nonvisual senses such as blindsense, blindsight, scent, and tremorsense can't discern or locate ethereal things.
Because the Ethereal and the Material Plane are coexistent, each point on the Material Plane corresponds with a point on the Ethereal and vice versa. To an observer on the Material Plane, a creature moving on the Ethereal seems to float along the Material Plane landscape. It also seems to move right through material objects and creatures. That's because most things on the Material Plane don't exist on the Ethereal.
Unlike an incorporeal creature, an ethereal creature doesn't have to stay adjacent to the object's exterior when it enters the object, so it can pass through an object of any thickness. An ethereal creature cannot see through opaque objects on the Material Plane; when within a material object, an ethereal creature cannot see anything on the Material Plane, though it usually can see other ethereal things.
An ethereal creature can hear sounds from the Material Plane. Unlike an incorporeal creature, it does not get a Listen bonus when it is inside a solid object.
Force effects extend into the Ethereal Plane, so a force barrier, such as a wall of force, blocks an ethereal creature.
The Ethereal Plane has no gravity. A creature on the Ethereal can move in any direction using its fastest speed rating. Hazards and obstacles on the Material Plane don't interfere with an ethereal creature's movement or damage the ethereal creature (but see Combat with Ethereal creatures).
An ethereal creature cannot touch, damage, move, or otherwise physically interact with things on the Material Plane.
It goes without saying, but ghost touch weapons an ethereal creature wields don't affect targets on the Material Plane. Spells and other magical effects that an ethereal creature uses don't have any affects on the Material Plane, and neither do extraordinary abilities.
Combat With Ethereal Creatures
Although ethereal creatures can't do anything to affect creatures on the Material Plane, the opposite isn't true. Any magical effect with the force descriptor extends to the Ethereal when it is created on the Material Plane (the opposite is not true). A caster can target a spell such as magic missile, for example, at an ethereal creature.
Because ethereal creatures can see into the Material Plane, gaze attacks used on the Material Plane also affect ethereal creatures. The rules don't mention it, but you reasonably can assume that a creature looking into the Ethereal Plane with a divination spell (such as true seeing or see invisibility) would be susceptible to a gaze attack from an ethereal creature.
Two ethereal creatures can fight and affect each other in the same way that two creatures on the Material Plane can, except that combat on the Ethereal Plane takes place in three dimensions.
Thanks to its manifestation power, ghosts get most peoples' votes for the most troublesome denizens of the Ethereal Plane. The most important thing to remember about a ghost is that it is ethereal, not incorporeal, until it uses its manifestation power to move onto the Material Plane. Once a ghost does so, it becomes an incorporeal creature on the Material Plane, though it also remains on the Ethereal Plane as well. Although the ghost template lists the ghost as an incorporeal creature, it is not incorporeal until it manifests and even then it is only incorporeal with respect to the things on the Material Plane. To anyone or anything on the Ethereal, even a manifested ghost is corporeal.
As a supernatural ability, manifestation requires a standard action to use. Once manifested, a ghost also can use a standard action to fully return to the Ethereal Plane.
With respect to the Material Plane, a manifested ghost functions just like an incorporeal creature as described in Parts Three and Four, except for two things: A manifested ghost can move through a creature or object of any size (thanks to its etherealness). A manifested ghost that has a magic weapon with it on the Ethereal Plane can use the weapon to strike creatures. A manifested ghost using a magic weapon that is not a ghost touchweapon is making an incorporeal touch attack. The ghost's Strength modifier doesn't apply to the attack roll (even for a melee attack) or to the damage roll. The ghost's Dexterity modifier applies to the attack roll. The attack ignores armor (except ghost touch armor). The attack has a 50% miss chance.
Ghosts and Ghost Touch Items
A manifested ghost using ghost touch equipment can do so either as a corporeal or an incorporeal user, depending on exactly where the ghost touch equipment is. If a manifested ghost finds a ghost touch weapon or ghost touch armor just lying on the Material Plane, it can handle and use that ghost touch equipment in exactly the same way that an incorporeal creature can. If a ghost on the Ethereal Plane has ghost touch equipment with it on that plane, however, then it uses ghost touch weaponry as a corporeal creature on the Material Plane does when attacking a foe on the Material Plane. (That is, the ghost has no miss chance, it makes a regular attack that must deal with the target's armor, and the ghost's Strength score applies to the attack and damage rolls.)
Against most attacks, ghost touch armor worn on the Ethereal Plane protects a manifested ghost the same way it protects an incorporeal creature. The ghost retains its incorporeal miss chance and gains only the armor's enhancement bonus to its Armor Class.
Against a ghost touch weapon wielded on the Material Plane, a manifested ghost still uses its manifested Armor Class, though there is no incorporeal miss chance. (The manifested ghost's equipment remains insubstantial against foes on the Material Plane.) If a manifested ghost wears ghost touch armor, the full value of that armor applies against a ghost touch weapon, and the ghost still gets its deflection bonus for being incorporeal. If the same attacker moved to the Ethereal Plane, the ghost would lose its deflection bonus to Armor Class.
The manifestation power can prove troublesome in a few circumstances. Take a look at some suggestions on how to deal with the worst cases.
Manifesting Inside Objects or Creatures: An ethereal ghost can move to an object's or creature's location on the Material Plane and then manifest so that it appears inside the creature or object. Treat this just like any other attempt to move through a creature or object, except, as noted earlier, the ghost doesn't have to stay adjacent to the creature's or object's exterior.
Malevolence: If the ghost has the malevolence power, there is no attack of opportunity when it enters a subject's space, and no touch attack is required if the subject has a deflection bonus to Armor Class. If the subject makes a successful saving throw against the malevolence attack, however, the ghost cannot enter the subject's space and must go back to whatever space it left to use the malevolence power. The attempt to enter the subject's space counts against the ghost's movement for the turn, but going back does not.
Returning to the Ethereal Plane: Because a manifested ghost can't exert any Strength on the Material Plane, it cannot grab things while manifested and drag them back to the Ethereal. It could, however, seize a ghost touch item and bring that back to the Ethereal Plane (where it could then handle the item normally). It's best to assume that a ghost can't use this trick with a ghost touch item in another creature's possession.
A dimensional anchor spell used against a manifested ghost has little effect because the ghost already is on both the Material Plane and Ethereal Planes. While the spell lasts, however, the manifested ghost cannot exit the Material Plane.
Next week, we'll consider the ins and outs of gaseous form.
About the Author
Skip Williams keeps busy with freelance projects for several different game companies and was the Sage of Dragon Magazine for many years. Skip is a co-designer of the D&D 3rd Edition game and the chief architect of the Monster Manual. When not devising swift and cruel deaths for player characters, Skip putters in his kitchen or garden (rabbits and deer are not Skip's friends) or works on repairing and improving the century-old farmhouse that he shares with his wife, Penny, and a growing menagerie of pets.
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