A Shade was a magic user and Sorcerer possessed by a spirit or spirits, thus becoming a new creature. While Shades could originally be Human, Dwarf, Elf or Urgal, once possessed they adopted similar traits, such as extreme strength and magic proficiency.
Shades were usually created when a sorcerer or sorceress summoned a spirit or spirits that he or she couldn't control and consequently became possessed by it or them in both mind and body. According to Angela, some magic users willingly submitted to the control of spirits in order to gain greater magical power, thus becoming a Shade.
In Brisingr, it was revealed that Shades could also be created by a sorcerer summoning spirits into the body of another, turning the recipient into a Shade. The incantations took several minutes and left the spellcasters vulnerable during the casting. To become a Shade, a humanoid form is not required. Many Shades have been formed, but most Shades self-destruct shortly after creation. Shades which survive the volatile natures of their formation were rare indeed.
Regardless of their original appearance, Shades become very thin and pale after their transformation. Their eyes and hair became dark red: Their eyes are maroon, "as red as wine" and their hair was crimson, "as red as blood." Shades resembled humans in other ways, with lean bodies "like a runner's, thin and compact." Durza was noted for his height and also for his nearly "translucent" skin. Shades could age, but this process was different to the aging seen in other species.
Since only an evil spirit would welcome the opportunity to enter and control the body of a living creature, Shades were altogether vile and cruel. Nevertheless, they were also intelligent and cunning, as well as skilled in magic and swordplay. They gained a reputation of terror and dread among humans as dangerous monsters and sorcerers: Reports of Shades disturbed traders such as Merlock and it was said that "rivers of blood" followed a Shade. Soldiers were expected to attack Shades on sight.
According to Christopher Paolini, it was nearly impossible for a Shade to be good because of the inevitably evil nature of the spirit. He also commented that the personality of the product Shade was an amalgam of the minds of the spirit and the spellcaster. He has also said that Spirits could possess any creature. It is likely that there were (or are) Shades of other genders and species, as Paolini has said that this area will be touched upon in Inheritance. It is said by Paolini that a Dragon or some other such creature may become a Shade in Inheritance and that Angela would be involved. The author was most likely referring to the story that Angela told to Nar Garzhvog regarding a red-eyed rabbit, as Shades are known to have red eyes.
Once created, Shades were extremely powerful and dangerous, among the most feared creatures in the world. In addition to sorcery, Shades were gifted with superhuman physical abilities, many times greater than the fittest humans. These abilities included supernatural strength, speed, stamina, pain tolerance, as well as unmatched senses: A Shade could see as clearly at night as they could during the day, track scents at great distances.
Perhaps their greatest ability was their resistance to death. A Shade could only be killed by being stabbed through the heart: otherwise, it would merely be temporarily disembodied and would reappear elsewhere in spirit form before returning to a body, healed. This process was unpleasant for the Shade and extremely painful, but had no lasting consequences. According to Ajihad, Shades were actually strengthened from being disembodied.
All Shades could use magic. Usually only sorcerers became Shades, meaning they would already have experience in using magic when they came into being. It is likely that Shades would become sorcerers anyway after being possessed, because of the magical nature of the spirits controlling them. The True name of a Shade would incorporate the true names of the spirits within.
Because they possessed greater strength and stamina than any human, Shades were more powerful in magic than human magicians and were able to cast spells that normally only Elves could use, as well as for longer than a human without exhausting themselves. Shades were known to practice the darkest kinds of magic. They are almost like shadows who can disappear and then reappear in an instant elsewhere. The word Shade has thus come from Shadow.
Shades were enormously difficult to kill. Only four people in the history of Alagaësia have ever killed a Shade and lived, thus being granted the title "Shadeslayer." One of these few was Eragon, who killed Durza with some help from Arya during the Battle under Farthen Dûr, and Arya, who stabbed Varaug in the heart with some help from Eragon during the Siege of Feinster.
(In the most likely order)
- Irnstad (Rider)
- Laetri (Elf)
- Eragon (Human Rider)
- Arya (Elf at time of slaying, later becoming a Rider)
A "shade" is an archaic term for the soul of a dead person which lingers like a ghost. In spite of their name, Shades bear more in common with modern western interpretations of vampires than with ghosts. Both creatures are created through magic and posess great power themselves. In addition, both can commonly only be killed by a strike through the heart, which in the case of a vampire is usually done by means of a wooden stake. Both are also typically difficult to kill.
Shades however lack the typical weaknesses of vampires. They do not fear the sun and seem to require little sleep, since Durza is never mentioned needing rest.
Like a vampire, Durza possessed sharpened canines, but his were filed to points, while a vampire's fangs are natural.