Invisibility

Invisibility is the ability to be invisible to only mortals.

Activation
Ghosts are the naturally invisible to mortals. Mortals are unable to hear, see or physically feel them. The only people that can communicate with ghosts are witches and warlocks.

Elyse

 * While Dash was still mortal Elyse visited him in the hospital but he was unable to see her.
 * In The Bent Elbow Freya was the only person who could see Elyse because Freya is a witch.

Adam Noble

 * At Adam's funeral Adam tried to talk to his family but no one could see or hear him except for Ingrid, Wendy, and Freya.