The Forsworn (Wyrdfell in the Ancient Language) were thirteen corrupt Dragon Riders with Galbatorix at their head. They spearheaded a rebellion "out of desire for power and revenge against perceived wrongs". This rebellion was later known as The Fall.
As of Inheritance, five of the thirteen original Forsworn have been named:
As of Inheritance, while five of the Forsworn's dragons were mentioned, only three of the dragons had their colour mentioned. None of the Forsworn's dragons could be named after the Banishing of Names, so they were referred to as their riders's dragon and, for example, the dragon that hatched to Morzan was known as Morzan's Dragon, or the dragon the hatched to Formora was known as Formora's dragon.
- Morzan's Dragon (red)
- Formora's Dragon (brown)
- Kialandí's Dragon (purple)
- Enduriel's Dragon (unknown)
- Glaerun's Dragon (unknown)
In a Random Buzzers interview in December 2011, Christopher Paolini revealed that four of the five mentioned Forsworn were elves. Since Morzan is known to be human, the remainder of the named Forsworn were all elven Riders.
Morzan was the first of the Forsworn. It was he who left a gate unlocked in Ilirea (later named Urû'baen), enabling Galbatorix to steal Shruikan and slaughter the black dragon's rightful Dragon Rider. Eventually, twelve more dissolute Riders came to support Galbatorix's cause. With their help, Galbatorix defeated the armies of the elves and dwarves, as well as murdered Vrael, head of the Riders. Two other Dragon Riders of the Forsworn, Kialandí and Formora, were mentioned in Brisingr, although not much is known about them.
At some point Kialandí and Formora captured the elven Dragon Rider Oromis and used a spell taught to Galbatorix by Durza's spirits. This spell isolated Oromis from the energy around him, effectively preventing his hold on magic. The spell was weakened by quick action on Oromis' part, but it stuck with him and prevented Oromis from gathering more than a small amount of energy at a time for the rest of his life. Oromis finally escaped from the Forsworn and went into hiding in Du Weldenvarden along with his dragon, Glaedr.
Eventually, the Forsworn died out due to in-fighting (they often vied among themselves for power and favor, something which Galbatorix encouraged and would often support one of the Forsworn over another for his own amusement), suicide, overuse of magic, as well as the efforts of Brom and the Varden. Morzan and at least two other Forsworn were personally killed by Brom: around five others died as an indirect result of Brom's zeal.
Glaerun and his dragon was the only member of the Forsworn to die in the fighting at Vroengard, having been killed alongside his dragon after their bodies were consumed by an explosion caused by another Rider, Thuviel, who had lost his Dragon to the Forsworn in the months previous to The Fall. Galbatorix and the rest of the Forsworn had a moment of warning and were able to shield themselves, and though the explosion killed Glaerun, his dragon and various Dragon Riders, it also rendered the land uninhabitable for the Forsworn.
In Brisingr, it was revealed that after the dragons who were not part of the Forsworn learned that their kin had betrayed them, they combined their magic together and performed the Banishing of Names, the Du Namar Aurboda, stripping them of their names. If someone looks at the name of any of the Forsworn's dragons or remembers their names, it is instantly forgotten.
The traitorous dragons lost everything that made them dragons. They became no more than beasts with magic they did not know how to use. Their Riders could only watch in silent misery as they sunk even further into beastliness. Five of the Wyrdfell's (elven name for the Forsworn) dragons became insane and several of the Forsworn went mad as a result.
The dragons spared Shruikan, because he was forced to serve Galbatorix, as well as Jarnunvösk, Galbatorix's first dragon because she had no part in this and the Eldunarí the Forsworn were using, as, like Shruikan, they were being forced to help the thirteen after witnessing those who had rider's partners deaths before being broken and buried in madness. Their descent into ignorance led to the popular misconception that dragons were little more than animals and transport for the Riders. After Galbatorix ascended to the throne, he rewarded his thirteen supporters with large plots of land and power for their services. However, throughout the years, the Forsworn died out throughout many different causes. The deaths included the following:
- Five dragons of the forsworn and a unknown number of the Forsworn were driven into insanity by grief after the Banishing of the Names. This is not a cause of death, but may have been a contributing factor.
- Killed during the power struggle amongst The Forsworn.
- Morzan and at least two more Forsworn members were personally killed by Brom.
- At least other five members of the Forsworn had their death's arranged by Brom.
- Committed suicide out of despair or madness (because their Dragons have become crazies?).
- Killed due to overuse of magic.
One hundred years later in a tragic irony, Murtagh followed his father's role as a servant of Galbatorix, however he was not considered one of the Forsworn.
The Forsworn may be compared to other groups of dark warriors from other popular fantasy sagas...
- The Sith of Lucas' Star Wars. Or also rather aptly could be compared to organizations of Dark Jedi in the service of the official Sith Lords including the likes of the Dark Acolytes from the time of the Clone War and/or the Emperor's Hands from the era of the Galactic Civil War.
- The Nazgûl of Tolkien's Lord of the Rings
- The Death Eaters of Rowling's Harry Potter series, in that they were corrupted by the promise of power.
- They are also similar to the Forsaken of the Wheel of Time, both in name, number (there were thirteen Forsaken, as well), and in the fact that they often fought among themselves for positions and status.
- They could also be put on par with the Witchmen of the Reach or also known as Forsworn from the Elder Scrolls series, who want revenge on the Nords.
- They're also similar to the Knights of Takhisis from Dragonlance, who also ride dragons and are devoted to evil.
- They’re also similar to the Nerverseen from Keeper of the lost cities, who are also a gang of villains ordered to kill.
- The fact that there are thirteen Forsworn may be a nod towards the fact that thirteen is generally considered to be an unlucky number - however this is unlikely since there are also thirteen Dwarf clans.