Shadow Dragons

Also referred to as Nightmare Dragons.

"It was like a shadow lingering around us (...) and that scream, it took us a few seconds to realize that it wasn't just the dragon. It also was us who were screaming."

Shadow Dragons are are unhoy creatures created by a freak accident, feeding on the fear of their victims and haunting the lands in their ghastly form.
Shadow Dragons can be created in two ways. Either when a dragon is killed and has the time and knowledge to curse its own blood or when a wyrmling drinks the blood of both its parents. However there seem to be a few exceptions to this.

Basic Information

Anatomy

They still resemble the features of their original sub-species like the form of their horns or wings. However their physical appearance seems to be in a state of decay with parts of their skeleton showing.
They are able to assume a gaseous form that resembles black mist. In this form they are able to fit even through the smallest openings.

Genetic Ancestor(s)