Creatures with the incorporeal condition do not have a physical body, but they are still within the Material Plane. Some ethereal creatures may be able to manifest an Incorporeal effect from the Ethereal plane to the material plane, but such things are rare and potent.
An incorporeal creature can be harmed only by other incorporeal creatures, magic weapons or creatures that strike as magic weapons, and spells, spell-like abilities, or supernatural abilities. It is immune to all non-magical attack forms.
Even when hit by spells or magic weapons, it takes only half damage from a corporeal source.
Although it is not a magical attack, holy water can affect incorporeal undead. Incorporeal undead also take full damage from Channel Divinity.
Corporeal spells and effects that do not cause damage only have a 50% chance of affecting an incorporeal creature.
Force spells and effects, such as from a magic missile or Ghost Touch weapon, affect an incorporeal creature normally.
An incorporeal creature's attacks are nearly always resolved as touch attacks, when made against corporeal creatures, as they pass straight through an enemy's natural and non-magical protections.
An incorporeal creature can enter or pass through solid objects, but must remain adjacent to the object's exterior, and so cannot pass entirely through an object whose space is larger than its own.
- It can sense the presence of creatures or objects within a square adjacent to its current location, but enemies have total concealment (50% miss chance) from an incorporeal creature that is inside an object.
- In order to see beyond the object it is in and attack normally, the incorporeal creature must emerge.
- An incorporeal creature inside an object has total cover, but when it attacks a creature outside the object it only has partial cover until the start of its next turn.
- An incorporeal creature cannot pass through a force effect.
Incorporeal creatures pass through and operate in water as easily as they do in air.
Incorporeal creatures cannot fall or take falling damage.
Incorporeal creatures cannot take any physical action that would move or manipulate an opponent or its equipment, nor are they subject to such actions. This includes nearly all combat maneuvers.
Incorporeal creatures have no weight and do not set off traps that are triggered by weight.
An incorporeal creature moves silently and cannot be heard with Perception checks if it doesn't wish to be.
Non-visual senses, such as scent and Blindsense, suffer a -10 penalty when attempting to perceive incorporeal creatures.
Incorporeal creatures have an innate sense of direction and can move at full speed even when they cannot see.
Some creatures, tied to shadow and darkness, have a lesser form of incorporeality, called nebulous.
Nebulous creatures take half damage from all attacks, including non-magical attacks, but only while the creature is not in an area of bright light. Furthermore, as with incorporeal, ghost-touch attacks, attacks by other nebulous or incorporeal creatures, and force effects, all deal full damage. Note that nebulous creatures deal only half damage to incorporeal creatures, as they are more corporeal than not.
Phased is a stronger form of incorporeality.
Creatures which are phased can only be hit 50% of the time with magic weapons, spells or supernatural abilities, and cannot be hit at all with mundane weapons or extraordinary abilities (unless the extraordinary ability is performed with a magic weapon).
Furthermore, a phased creature takes only half damage from all damage sources. On any effect which normally inflicts half damage on a successful save, a phased creature takes only one quarter damage if they succeed on that save. Note that this applies to any such attacks, spells, or effects, regardless of which saving throw (FORT, REFL, or WILL) they target.
Spells and effects that do not cause damage only have a 50% chance of affecting a Phased creature.
As with Incorporeal creatures, force effects, other incorporeal creatures, and ghost touch weapons deal full damage against a Phased creature, but only if they successfully hit.