The Nocturnal ectophial is a teleportation reward for completing the Til Death Do Us Part event. It is described as 'an evil vial filled with shadows of ectoplasm' but Death isn't quite sure if the substance is even ectoplasm anymore. When used, the Nocturnal ectophial provides an instant teleport to the shadow realm of the event. Only one can exist in the player's inventory or bank at a given time. It can be reclaimed by obtaining an Ectophial and using it on Death, where he sells you nocturnal shadow for 1,000,000 GP.