Arcann

"Destiny is a lie."

- Arcann's belief

Arcann is the son of the "Immortal Emperor" Valkorion, the twin brother of Thexan and the older brother of Vaylin. He is the main antagonist of Star Wars: The Old Republic - Knights of the Fallen Empire.

Early Years
Arcann and his twin brother Thexan were both princes of the Eternal Empire born to Valkorion, the "Immortal Emperor" of the Eternal Empire, and Senya Tirall, a member of the Knights of Zakuul. As the boys grew older, they began to adore their father and show less affection for their mother. But when the children started training to become warriors, Arcann slowly started resenting Valkorion for his lack of interest or concern towards his family, ignoring them for weeks at a time.

When Arcann's younger sister Vaylin was born and started showing her unstable power over the Force, which she inherited from her father, Valkorion placed mental blocks that suppressed her power but also deeply damaged her personality. This act made Senya decide to leave with her children, only for Arcann and his siblings to refuse to go with her and scorn their mother's concern towards them. Broken-hearted and knowing she can't stop her children, she instead returned to the Knights in the outer fringes of the Eternal Empire, never to speak with Valkorion or her children again.

Fratricide
Later, when the boys had reached adulthood, Arcann and Thexan approached Valkorion with the proposal of attacking the border worlds of the Eternal Empire and eastern galaxy. While their father sanctioned the attacks, he only allowed Thexan to lead the Eternal Fleet. Prompting an angered Arcann to disobey Valkorion's command and accompany his brother anyway in their attacks on the Galactic Republic and Sith Empire. During their attack on the Sith homeworld of Korriban, Arcann was critically injured in battle, losing an arm and suffering severe scars on his face. Resulting in him gaining a cybernetic arm and mask covering the left half of his face. When Thexan reported Arcann's injuries to Valkorion, he showed little remorse for his son, deeming it a fair price for disobeying him.

Returning to Zakuul, Arcann and Thexan placed their trophies from the raids before their father. However, Valkorion only responded in silence and turned away. Enraged by his father's lack of caring, Arcann became overcome by the dark side and leapt at Valkorion in an attempt to kill him. But Thexan used the Force to pull Arcann back and tried to stop him, only for Arcann to accidentally kill his twin brother in a blind fit of rage. As a horrified Arcann came to his senses and realized what he had done, an unmoved Valkorion approached his son as he cradled his brother's body and instructed Arcann to come with him.

Usurping the Eternal Throne
"People of Zakuul. The unthinkable has happened. Our beloved Emperor, Valkorion, is dead—murdered by an Outlander who sought to shake the foundations of our great society. The assassin will receive swift and just punishment. And this act of unprovoked aggression will be answered. As your new Emperor, I can promise you this: Zakuul's enemies will face the full power of the Eternal Throne. They will answer for their warmongering ways. And every last one of the Core Worlds will burn."

- Arcann declaring himself the new Emperor of the Eternal Empire

When Darth Marr led a joint Imperial-Republic fleet into their territory, Arcann informed his father of their presence, but Valkorion was already aware, and sent the Eternal Fleet to intercept the expedition. In the aftermath of the battle, the expedition was destroyed and Arcann's forces captured Darth Marr and an Outlander to be brought directly to Valkorion on Zakuul. Before Arcann can escort the two to the Eternal Throne room, he is apporached by the Scion Heskal, who informs Arcann that the Outlander is dangerous. Arcann brushes aside this warning and brings the two captives before Valkorion, who offers to share his power with the two if they simply kneeled before him. Darth Marr bluntly refused to serve Valkorion again and is quickly executed after attacking the Emperor's guards. Vaylin then ordered everyone to exit the room except for Valkorion, Arcann and the Outlander, who Valkorion once again reiterated his offer towards.

However, Arcann betrays his father at that very instant and Valkorion is struck down, with Arcann assuming the Eternal Throne in his place. As the new Emperor of the Eternal Empire, Arcann used his father's murder as an excuse to launch an attack on the Core Worlds. However, sensing that Valkorion was still alive and inhabiting the Outlander, he had the outsider frozen in carbonite.

Arcann's war was swift and brutal. Within months, he had forced the Galactic Republic and Sith Empire into submission. Both sides, represented by the Galactic Senate and the Minister of Logistics respectively, formed treaties with Zakuul, promising regular tribute, which was more than needed for the Eternal Empire, which Arcann had unspecified plans for. For all intents and purposes, Arcann held dominion over the galaxy. He ignored the animosity between Republic and Empire, who were more intent on fighting each other than uniting against Arcann. Meanwhile, Arcann's rule over Zakuul had become corrupt and oppressive. He executed a great many Scions, who used to be partnered with Knights, driving the survivors into exile and allowed the heretical Heralds of Zildrog rule the Old World before implementing so many restrictions that effectively left them powerless

Hunting the Outlander
Five years later, Lana Beniko and Koth Vortena successfully freed the Outlander and fled from Zakuul, to Arcann's displeasure. He sent forces after them into the Endless Swamp but the rebels managed to find the Gravestone, the legendary starship that once overpowered the Eternal Fleet, destroying more than two dozen ships in the process of their escape.

Vaylin later informed Arcann that the Outlander had returned to Zakuul and was spotted in the Old World. Arcann publicly informed the denizens of Old World to watch out for the Outlander. Later, when the Outlander fled Zakuul, Vaylin revealed that after questioning and executing three Knights, that she learned their mother Senya had allied herself with the Outlander, but Arcann replies that if she's now against them she will face the consequences.

Battle of Asylum
Arcann later learned of the Outlander's hideout on Asylum from Heskal, who desired to fulfill the prophecy that the Outlander would be his downfall. When the Outlander arrived at the Scions' hideout, Heskal was standing over the bodies of five Scions, before Arcann fatally impales him. He then extends the Outlander an offer: In exchange for going back into carbonite until he finds a way to exorcise Valkorion and the surrender of the Gravestone, he would allow the Outlander's allies to leave.

His terms were refused, resulting in an all out battle on Asylum. Arcann's fight was interrupted by a crashing shuttle, allowing the Outlander to flee the scene. He followed the Outlander to the docking port and engaged his foe again, destroying HK-55 in the process. But once again, the Outlander managed to defeat Arcann and escape aboard the Gravestone. Arcann then reunited with Vaylin, informing her that Valkorion's power had diminished.

Personality
Arcann was a calculating, shrewd, patient and ruthless young man. Arcann deeply desired love and acknowledgment from his father, Valkorion, but his father's lack of interest in his children caused Arcann to develop a deep resentment for his father, to the point that in a fit of rage, Arcann attempted to kill him.

Arcann and Thexan were inseparable as children, with Thexan helping Arcann in times of need and Arcann having complete faith and loyalty in Thexan. When Arcann had lost his arm, Thexan never left his side, something Arcann deeply appreciated. After accidentally killing Thexan, Arcann was shocked and heartbroken by his actions, and it is implied this is the one action he has taken that he regrets. Arcann later speaks of missing Thexan to their sister, Vaylin, believing that Thexan would've sided with him against their father. Arcann also appeared to love Vaylin, and his acknowledgment of her abilities kept her loyal to him.

However, Arcann is just as arrogant as his father, believing himself to be beyond the reach of destiny, and that the visions of the Scions do not affect him. This belief drives him to hunt the Outlander in order to prove them wrong.

Powers and Abilities
As the son of Valkorion and Senya, Arcann was a naturally strong in the Force and a highly skilled duelist, capable of defeating both Sith Lords and Jedi Knights. Arcann also had skill in politics, making Zakuul the most powerful political faction in the galaxy after taking over. He also showed talent as a strategist and military commander, defeating both the Galactic Republic and Sith Empire within only 5 years.

Trivia

 * Arcann is similar to Zuko from Avatar: The Last Airbender: They are princes who were abused by their fathers and the older brothers of deranged princesses. They even have facial scars. However, Zuko eventually redeemed himself, whereas Arcann killed his father.