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This article contains plot details from the latest books.
Alvar Soren Vacker is the older sibling of both Fitz and Biana Vacker. He is a Vanisher like his mother Della. He doesn't live with the family anymore and is living as a fugitive. In Book 8, he is found to be living in Candleshade. In Book 1: Keeper of the Lost Cities, he was working to keep peace with the ogres, who were getting angry about the smoke from the fires in the Forbidden Cities. His personality is very smug and aloof, and he is a ladies man, once juggling 3 girlfriends, much to Della's horror and Keefe's amusement. Della often tells the group of how she kept Alvar in line for years.
As of Book 8: Legacy, he has given up and is ready to die.
The name "Alvar" means elf army, "Soren" means 'solemn.'
Alvar has dark wavy hair, usually immaculately styled, cobalt blue eyes, that were later, since Nightfall, mentioned being pale blue. In addition, he was mentioned to have a square jaw. It is said in Book 7: Flashback that he had gained curved red scars on his neck, face, and arms after being cut by a shamkniv. After escaping the hives, his appearance became haggard.
Alvar makes his first known appearance at a dinner taking place at Everglen after midterms. Sophie was unaware that Fitz and Biana had an older brother. He later told Sophie that the sign on Grady's scrolls was the sign of the swan. He stated that the Black Swan was a hoax.
Sophie comments that Alvar clearly worked hard to look good, unlike his parents and siblings who were effortlessly handsome/beautiful.
When Alden's mind broke from grief after seeing Wylie dancing at Foxfire, Alvar was the one who told Biana the news. He seemed calm, helping Della, Fitz, and Biana cope with Alden's condition. He helped Sophie understand why Fitz was reacting the way he was. Alvar seemed to be helpful to Sophie by encouraging Biana and Fitz to understand that it wasn't Sophie's fault his father's mind had broken.
Alvar is revealed to have been part of the Neverseen since he was in Foxfire. He has been a spy for them and has been passing along information from his father, Alden. Alvar believes that Fitz is his father's favorite son and that he has to live up to the "Golden Boy."
It was also revealed that Alvar was in fact 'The Boy Who Disappeared', seen by Sophie during her childhood. During this time Alvar was being sent by Alden to search for the moonlark (Sophie) in the Forbidden Cities.
In Lodestar, Alvar is frequently mentioned by Keefe while the latter was with the Neverseen. Apparently, he had many crazy theories about the identities of Mr. Forkle. During the confrontation at the Pallidrose hideout, Keefe takes Tam's leaping crystal and brings Alvar to Alluveterre. Alvar was not present at the fall of Lumenaria.
In Nightfall, Alvar is found unconscious in Lady Gisela's newer Nightfall and has been tortured with a shamkniv. They find out that he is unconscious because he was exposed to soporidine. At the end of the book, when given the antidote to soporidine, he wakes up with no memory of the fact that he was a member of the Neverseen and that he helped kidnap Sophie, and the book ends with Alvar saying "Who's Alvar?"
In Flashback, Alvar still has no memory of his past life, confirmed by many telepaths. He is sent by the Council to live at Everglen once again, with a guard, to see if he is telling the truth. He will live in his own apartment on the grounds. Alvar says that he would never rejoin the Neverseen, instead of saying he'll do anything in his power to stop them and shows the scars on his arms, given by the Neverseen as proof. At Everglen, on the eclipse, Alvar gets his memories back. He rejoins the Neverseen. Fitz attempts to knock him out when he sees that he is moving towards the gate, but he is unable to do so due to Sophie's null blocking the Warden. When they get back and see that Alvar is evil again, Fitz once again tries to knock him out but is unable. Finally, he lets the Neverseen in, resulting in them being able to release the trolls, almost killing all of Sophie's friends. They give him multiple chances to leave the Neverseen, but he refuses. He is knocked into one of the hatching pods and Fitz and Biana frantically press buttons to lock him in but stop when the pod starts to fill with liquid. They think he is dead, but later find that he has escaped once again.
Alvar is found hiding at Candleshade by Keefe and Sophie and he claims that he's dying after being in the troll goo. They decide to let him go in exchange for information.
- ALDEN (father)
Alden is Alvar's father. Alden and Alvar seemed to disagree on many things on many levels. When Alvar was younger he helped his father by searching for Sophie in the Forbidden Cities. As he aged, Alden replaced him with Fitz since Fitz was closer to Sophie's age and Alvar was having trouble with sneaking out of the Silver Tower. Alvar felt that Fitz was always his father's favorite and needed to live up to "Wonderboy".
- DELLA (mother)
Della is Alvar's mother. She is a vanisher, like him. In Keeper, he brags about having three girlfriends, much to Della's distaste. She frequently mentions to the group that she "kept Alvar in line for years".
- FITZ (younger brother)
Fitz is Alvar's younger brother. Alvar has always felt that Fitz was Alden's favorite son. When Alvar was revealed as a member of Neverseen, Fitz was angry beyond words. He is shown to be a little jealous of Fitz in Neverseen. Fitz nearly killed Alvar in Flashback, and never forgave him even during his mind-wiped phase. Fitz's defense for trying to kill Alvar was that "he's a murderer", even though he has only been confirmed to have attempted murder and it has not been specifically stated that he has succeeded.
- BIANA (younger sister)
Biana is Alvar's younger sister and he seems to have a soft spot for her. When she learns that Alvar is part of the Neverseen she says "How could you?" His expression softens as he explains, showing that he cares for her more than Fitz and the others. For unknown reasons, he also believed that she would understand about the Vacker Legacy.
- KEEFE (former friend/enemy)
Keefe admires Alvar and later works with him and the Neverseen. Alvar doesn't believe that Keefe needs as much watching as the other members of Neverseen do because Alvar knows Keefe through Fitz and Lady Gisela.
- BRANT (Former Ally)
- FINTAN (Leader)
Works with him in the Neverseen.
- SOPHIE (enemy)
The target of kidnapping. He also saw her when she was five, startling her so much she fell on her head, causing her to prematurely get her telepathy. She was acquaintances/friends with him in Neverseen before he was revealed to be a member of the Neverseen group.