Not much is known about Arion's early life, except that as a Prince of the Elves he would have been raised in the palace at Arborlon.
Prior to the events of the Shannara Chronicles, Arion's brother Aine was killed at the hands of the Gnome assassin Slanter, making Arion the new heir to the throne. His brother Ander, wracked by guilt, turned to alcohol to cope. Ander's relationship with Commander Diana Tilton suffered due to his behavior, and as a result Diana left him and moved on to a relationship with Arion.
The War of the Forbidding
When Amberle returns to Arborlon after spurning her duty to the Ellcrys, Ander is the first to show his support for her, while Arion does not. Ander also trusts his father's judgment and the advice of the Druid Allanon to aid Amberle on her quest to restore the Ellcrys, whereas Arion distrusts the Druid and advocates for a military solution to the problem of Demons that the Elves are facing.
Eventine had been intending to abdicate the throne to Arion, and Arion, believing he deserves the crown, urges his father to do so when the extent of the problem posed by the pending onslaught of Demons becomes clear. However, Eventine's belief that no king should abdicate in the middle of a crisis, coupled with his observations of Arion's distrust of Allanon and harsh words for Amberle convinces him to stay on the throne longer.
Without the knowledge of the King, Ander also frees Slanter from the prison he'd been languishing in since Aine's murder in return for his assistance and the assistance of the Gnomes in the fight against the Demons. While Arion is initially furious when Ander suggests freeing Slanter, he allows Ander to carry out his plans.
It is during another discussion with Arion about giving up the throne that Eventine is killed by the Changeling, which had taken on Arion's form. The Changeling then assumes Eventine's form and orders Arion to retrieve the Warlock Sword from the tunnels beneath Arborlon and use it against Allanon.
After Arion uses the sword against the Druid and Allanon is presumed to have been killed by the blade, the false Eventine orders Arion and Ander to fight the Dagda Mor alone, using the Warlock Sword. Upon facing the two brothers, the Dagda Mor reveals that Arion had done his bidding by recovering the sword and killing Allanon, and that Eventine has already been killed. The Dagda Mor then spirits the sword away from Arion before killing him with it. Ander, who is saved by Allanon, returns to the palace and kills the Changeling. With the deaths of Eventine and Arion, Ander becomes the King of the Elves.
Later, during the last stand against the Demons to protect the Gardens of Life, Commander Tilton is caught off-guard when a Demon's helmet falls off and she sees that the Demon is actually Arion. It becomes apparent that Arion, after being stabbed by the Dagda Mor, had his mind taken over by and was forced to fight for the Demons.
Diana's moment of hesitation is enough for the Demon-influenced Arion to have time to kill her with his sword. When Arion is later confronted by Ander, he has a moment of lucidity and begs for his brother to kill him. Ander, though distraught, complies with his brother's wish, freeing him from his mental prison.
Like most young men, Arion was very arrogant, prideful and egotistic, this was evidenced by the fact how he spoke down to his father in a disrespectful manner, regarding how to find the blood fire to restore the Ellcrys, Eventine also refused to step down as king of the elves, after realizing that not only was Arion immature, but he was also not ready to become the next king yet.
Arion was impatient when it came to the supernatural, evidenced by the fact when Allanon was explaining that the Ellcrys was dying and a demon army was slowly being released, he was also hostile towards Allanon and Wil Ohmsford respectively for no apparent reason, simply due to their human heritage (albeit Wil is a human-elf hybrid).
Arion's pride and ego was to the point that he wanted his father's approval, because of this, he did not realize that the Eventine was speaking, was in fact a changeling (who had killed the real Eventine and taken his place) this was also what led to Arion's downfall and death at the hands of the Dagda Mor.
Changes made for the TV Adaptation
- Aine is killed in combat by Slanter during an attempt on Eventine's life, making Arion the new heir to the throne. In The Elfstones of Shannara, Aine is killed in a hunting accident.
- Repeated references are made to Aine having been the firstborn son and the heir to Eventine's throne, making Arion the middle son and Ander the youngest son. In Elfstones, Aine is the youngest son, Arion is the oldest and the heir apparent, and Ander is the middle son.
- Arion is portrayed as being serious and dutiful, compared to Ander who is a bit of a party boy; in Elfstones it is Ander who is the quiet, serious son, while Arion is portrayed as a dashing and handsome athlete and fighter.
Arion Elessedil is a character in The Elfstones of Shannara. He was the Crown Prince of the Elves and the oldest and favorite son of the Elven King Eventine Elessedil. He was the older brother of Ander Elessedil and Aine Elessedil, and uncle to Aine's daughter Amberle Elessedil.
Aine and Arion were very close, but when Aine died eleven years prior to the events in Elfstones his daughter Amberle went to Ander for support and comfort, arousing jealousy and bitterness in Arion and beginning a conflict between the two surviving brothers. Seeking seclusion, Ander moved out of the palace but remained in the Elven city of Arborlon.
Arion's hostility towards Ander grew when Amberle fled her home and deserted the Ellcrys, thereby disgracing the entire Elessedil family. He blamed Ander's influence for Amberle spurning her duties as a member of the Chosen
When Amberle returns to Arborlon and is brought before Eventine's advisors by the Druid Allanon, Ander is the first to stand with her while Arion tells the Druid to send her away. Ander ends up supporting Aine's daughter on her quest to restore the Ellcrys, while Arion votes against Amberle being reinstated as a Chosen.
When the Elves came under attack by the Demons, Arion was given command of the detachment preparing to defend Worl Run in an attempt to stop the Demons from flanking the main army at Halys Cut. During the battle, the Elven standard fell. Arion tried to recover it, but was killed during the attempt. He was buried in the land at first light without any grave markers to prevent the Demons from desecrating his grave. With Arion's death at the Worl Run and with Eventine gravely wounded at Halys Cut, Ander is forced to lead the Elves and he commands the combined forces in the fight against the Demons.
After the Forbidding was restored, Ander had become King of the Elves. He was the last of the House of Elessedil alive: Eventine had passed way from mortal wounds, Arion had been killed in battle without leaving behind any children, and Aine was long dead with his only child Amberle becoming the new Ellcrys.