Role in Eragon
Sloan refused to accept Eragon's "stone" as payment for meat when Eragon asked him to see how much it is worth because Eragon revealed that the stone came from the Spine, which Sloan believed to be cursed. His wife, Ismira, had met her terrible fate there years before, by falling over a waterfall, and he wanted nothing to do with it. In the book, Horst and Katrina interfered and Horst paid for Eragon's food. Sloan unhappily gave in. Later, he told the Ra'zac who Eragon was, where Eragon lived, as well as that Eragon had Saphira's egg or the "stone". In the movie, he does this only because he was threatened and even attacked: thus, in the book, it is possible that they threatened him or Katrina before the snippet of dialog that Eragon overheard.
Role in Eldest
When the Imperial forces came to Carvahall seeking Roran, Sloan joins the village in fighting them, but when Katrina tries to take refuge in the Spine, he becomes enraged and attacks her, as well as tries to drag her home. Roran hits Sloan and rescues Katrina, as well as reveals that they are both engaged. Sloan is furious that they became engaged without his permission and tries to convince Katrina to come with him. Hysterical when she chooses Roran, he disowns her and denies her her mother's inheritance. Later that night, he betrayed the townspeople to the Ra'zac in order to regain control over Katrina and murdered Byrd because he was on watchman duty. He was then kidnapped, along with Katrina, by the Ra'zac and is not seen again until Eragon discovers him at Helgrind later on.
Role in Brisingr
Sloan and his daughter are held captive by the Ra'zac in their lair at Helgrind and Roran, Eragon and Saphira set out to save Katrina. They succeed in killing the last Ra'zac and Lethrblaka, but Eragon is faced with deciding Sloan's fate.
Sloan has been tortured by the Ra'zac into revealing all he knew about Eragon and had his eyes gouged out. Though Eragon knows that killing Sloan quietly would be the merciful thing to do and the easiest way out of his conundrum - Sloan, after all, betrayed the village of Carvahall - Eragon cannot bring himself to cold-bloodedly murder anyone helpless. Eragon lies to Roran and Katrina and says that he had found Sloan's dead body. Roran in turn informs Katrina of this and she closes her eyes and becomes pale.
Eragon dangerously stays behind to lift the sleeping Sloan and himself down the towers of Helgrind, exhausting his energy and letting Galbatorix's horsemen get very close.
However, Eragon must still decide upon a fitting punishment for Sloan. As they reach the desert, Eragon discovers Sloan's true name and uses it to put several spells on him to force him to travel to Du Weldenvarden. The magic condemns him to never see his daughter again, the one person he is devoted to. This compulsion can't be lifted however, even though Eragon invokes his true name and forced him to swear to never see his daughter again, because he promised the oath in the ancient language and so it is impossible for Sloan to see Katrina again, unless Eragon releases him from his oath.
Sloan currently resides in Ellesméra under the care of an elf, as when Eragon went to visit him, Sloan thought it was a music-playing elf trying to lift him out of his misery.
Role in Inheritance
In Inheritance Eragon met with Sloan for the last time (though Sloan initially thought that Eragon was Adarë) and restored his sight so that he could see his daughter and granddaughter. He could not contact them in any way, but he was still grateful to be able to see them.
Sloan was a small man, with scars covering his hands. His hair later turned white during his imprisonment. After his eyes were plucked out, his damaged eyelids were still attached and his tear ducts still worked.
Shall I gut and hamstring you?— Sloan, during the Battle of Carvahall
As shown by his shop, Sloan is a man who keeps tight control over the things surrounding him and takes enjoyment in doing so. Though he dotes on Katrina, he also attempts to control her, as shown in both Eragon and Eldest. He also apparently cared about his wife, as it was her death that caused his paranoia regarding the Spine. In Eragon chapter Palancar Valley Horst describes Sloan as being a "vicious troublemaker".
Sloan despised Garrow, Roran, as well as Eragon due to the fact that he looked down on them because they were farmers, with this, in turn, coming from Sloan having had an attitude of classism towards Garrow, Roran and Eragon. He is very proud, paranoid, possessive, as well as obsessive when it comes to his daughter Katrina. During Eldest, he seems almost psychotic, as well as is highly temperamental:
- In battle, he is a bloodthirsty man, cleaving through soldiers' helmets with his cleavers and slightly psychotic as he kills. See above quote.
- He insists that Katrina not go into the Spine and when she defies him, he becomes enraged.
- When attempting to force her to remain in Carvahall, Sloan is approached by Roran, who tells him that the trip to the Spine must go forward and that he and Katrina are engaged. Sloan tries to tackle Roran, but instead ends up getting punched in the face.
- Sloan then disowns Katrina and runs home in tears: soon afterwards, he betrays all of the villagers, resulting in Byrd's death and Katrina's and (ironically for him) his own capture by the Ra'zac, his and Katrina's rescue by Roran, Eragon and Saphira; Sloan's punishment from Eragon for the part Sloan played in the death of Byrd and events leading up to his and Katrina's capture despite his and Katrina's rescue.
Yet despite his confrontational attitude and behavior, Sloan was also a coward at heart as evidenced when the Ra'zac turned on him as he became frightened (and likely plead for mercy) as well as his terror when Eragon reveals both his power and status as a Dragon Rider to him while he is imprisoned. After his true name was revealed by Eragon, he fell into despair and pleaded/demanded Eragon to kill him so he would not feel pain anymore and fell into a childish temper-tantrum when refused while still cowering in fear. When Eragon confronted him for a final time, Sloan threatened violence despite shivering uncontrollably; showing the coward he had always been, the kind who hides his fear behind anger.
Relationship with Ismira
Sloan had great mutual love for his wife, and during their marriage they had a single child named Katrina. While Katrina's relationships with her parents were initially whole and healthy, Sloan later became obsessive after Ismira's death. In Brisingr, chapter To Walk the Land Alone, Sloan mumbles: "… only a piece of rope. I didn't mean to… Ismira…No, no, please no…", which may imply that he was involved in and blames himself for her death.
Relationship with Katrina
Sloan used to love his daughter as a normal father might love his daughter. However, his wife's death forced him into solitude and his daughter was the only person he spoke to on a regular basis. He grew to love his daughter obsessively: watching her all the time and trying to control everything that she did.
Katrina loved her father deeply, but was irritated at his immature and childish behavior, especially when it came to Roran, Eragon and Garrow, as well as Sloan's classist behavior towards the three of them.
When Eragon attempted to sell the dragon egg he found to Sloan, Katrina tried to convince her father to buy it and Sloan spoke harshly to her, which in turn made her treat him coldly. Eragon was shocked that Sloan treated her that way, as Sloan always treated Katrina with love. But when the subject of the Spine came up, Sloan was always tense and angry.
In Eldest, Sloan was planning to marry Katrina off to someone of his own choosing against her will, determined she would have a man that deserves her in his own mind. When Roran mentioned his plan to move the woman and children to the Spine to protect them, Sloan was adamant that they should not enter it. When the other villagers agreed, Sloan was furious and stated that no one of his blood should enter the Spine.
When Roran convinced Katrina to go, Sloan became furious and manhandled her and tried to drag her to the house. Roran saved her and he and Sloan exchanged blows. Katrina was forced to choose between them and she chose Roran.
Sloan was broken-hearted that Katrina has broken free of him and his control. He disowned her and denied her her mother's inheritance, but when that did not convince her to come back home, he spoke with the Ra'zac and promises them that he will help them into the village if he and Katrina are spared.
Sloan then stabs Byrd in the back, who was on watchman duty, and assists the Ra'zac and soldiers in kidnapping Katrina. He is happy and ecstatic to have won over hi daughter; however, when the Ra'zac double-cross him and take Katrina and him with them as hostages, he is angry and even more frightened.
Sloan is doomed to never see his daughter again after he and Katrina are rescued by Roran, as well as Eragon and Saphira, after which Eragon invokes Sloan's true name, has him go to Ellesmera and then even after his eyes are replaced, his vision restored Sloan is bound by an oath in The Ancient Language to Eragon that he can at least see his daughter from a distance but is otherwise to never see his daughter through visiting her, ever again and that causes him much grief, for though he was cruel very often to her, he still loves her very much.
Relationship with Eragon
Sloan despised Eragon and looked down upon and treated him horribly whenever he came into his store for meat, with this attitude and behavior coming from his classist attitude toward Eragon, as well as Roran and Garrow. When he found that Eragon was truly a Dragon Rider, he was afraid, yet hid it behind his anger upon finding this out and horror and shock. He refused to admit regret for Byrd's death to Eragon, and when Eragon put his sentence upon Sloan, stating that Sloan brought this upon himself and that this was his - Sloan's - punishment, Sloan was tormented to know his true name and heart-broken that he would be banned from his daughter's presence forever, even when his eyes were grown back and his vision restore, after which he would learn that Eragon would alter the oath he has Sloan bound to when he tells Sloan that he can see from a distance but can still never show his presence to his daughter or his granddaughter, ever at all and ever again.
Relationship with Roran
As with Eragon, as well as Garrow, Sloan always despised Roran and treated him unkindly due to his classist attitude towards people like Eragon, Garrow and Roran. Roran was determined to please Sloan and was always polite with him.
However, when he and Katrina become engaged and Roran failed to forewarn Sloan about it, Sloan was furious. He and Roran came to blows over Katrina and then Sloan forced her to choose between them and she chose Roran.
Sloan hated Roran bitterly several times more, and after he lost his eyes and Eragon informed him that Katrina and Roran will always be safe from him, with it being true even when Sloan got his eyes grown back and his vision restored - after which Sloan was to only see them and his granddaughter from a distance and otherwise never show himself to them again, Sloan wept in grief, failing to understand that he brought this to himself.