Intangibility

Intangibility, also known as phasing, is the ability to alter one's molecular structure to a state that can pass through physical matter; rendering the user immune to many physical and magical attacks. For certain magical beings, such as spirits, being non-corporeal is a natural state of being.

List of beings who use(d) Intangibility
Original power Through spell, potion, magic dust, etc. State of Being
 * The Source of All Evil
 * Leah
 * The Avatars
 * Barbas
 * Tuatha  (Through her magical dust)
 * Chris Halliwell (dark future)  (When he was fading out of existence.)
 * Spirits  (Can become corporeal through Corporealization.)
 * Jonathan Davies
 * Muses  (Can be made visible and corporeal with a spell and possibly by choice.)
 * Angel of Death  (Can become corporeal by choice.)
 * Phantasms
 * Cole Turner  (In the Cosmic Void)
 * Sandmen