Viren is introduced as the High Mage of Katolis, the best friend and closest advisor of King Harrow, and the father of Soren and Claudia.

In the second season, he fails to unite the other four human kingdoms against the elves and dragons, and allies with Aaravos, a mysterious Startouch Elf who communicates with him via a magic mirror that previously belonged to King Avizandium.

Despite making Viren the story's villain, Ehasz and Richmond wrote him as a "flawed [and] complicated" pragmatist because they felt this moral ambiguity made the character rounder and more interesting, providing better storytelling opportunities.

Critics gave Viren positive reviews and many praised the character as one of the show's best, and his ambiguous morality has often been the subject of attention.

Many critics said it makes him a compelling character and villain, and praised the show for encouraging its viewers to ask whether Viren's actions are justified.

Viren traps them in ice, and Tiadrin persuades him to spare the egg by appealing to his need for powerful ingredients for dark magic spells.

As a token of "gratitude", Viren traps both their spirits inside cursed coins, and takes the egg and an enchanted mirror from the lair.

He is shown to have been displeased at his eight-year-old daughter's consistent mishaps due to her determination to fully understand and master dark magic, as he does.

When Claudia is summoned to the Throne Room for her troubles in the castle, King Atticus (Ezran's paternal grandfather) has her practice in Lord Viren's hidden chambers instead, which she agrees to.

Unaware that his daughter had been eavesdropping, High Mage Viren informed the King that he was fine as was expected of him, given that his nine-year-old son was terminally ill and that his wife Lissa had recently left him shortly after Soren was magically healed some time ago.

[9] Viren presents a two-headed Soulfang Serpent, a cobra-like snake that can drain people's souls, which he proposes to use to switch King Harrow's spirit with that of another and save his life.

Queen Khessa's attempts to purify Viren of his dark magic give him and Aaravos access to the Sun Forge, the source of their power, and they corrupt and seize it.

Claudia finds Viren's broken, lifeless body and revives him with dark magic albeit with great difficulty, taking two long years, and together they watch Aaravos' caterpillar pupate inside its cocoon undergoing metamorphosis.

Having misgivings about Aaravos' promise to sustain his new life permanently once he has his freedom, Viren attempts to explain that he is no longer certain whether he wants to live again and spend his last thirty days alive with Claudia.

Being told that he had left his dark magic staff on the Storm Spire's pinnacle, Viren began to experience flashes of post-traumatic stress from his last encounter with the Moonshadow Elf Rayla.

As the days pass and "the Being" leads his group to the first piece of the ancient puzzles to Aaravos' whereabouts by stopping at Umber Tor to see the Archdragon of Earth, Viren is reunited with his estranged son.

When Claudia succeeds in stealing the map leading to Aaravos' prison, Viren approaches the staff hesitantly but touches it for the first time in two years, causing him to become swayed by its dark powers again.

Outside in the sunlight's warmth, his eyes glow blue-white and his face is wrinkled with the thoroughly draining effects the dark magical features have on his body and mind yet again.

Having touched his staff for the first time in two years, he is overcome by its tempting dark powers once again, which immediately starts to take a renewed toll on his already conflicted psyche.

In this dream, Viren is confronted by painful memories of his own past regarding his lifelong obsession with dark magic and the ramifications his ambitions had caused over the years and begins to have misgivings about releasing Aaravos.

They work together to create a new primal moonstone as part of Aaravos' plan to invert the Moon Nexus and free the spirits of the dead into the living world.

Claudia comes to later realize that her father's spirit has passed on, as he died saving the citizens of Katolis and redeeming himself, but continues to aid Aaravos now that she is too far gone.

According to series co-creator Aaron Ehasz, Viren was one of the first two characters to be created for The Dragon Prince, alongside his son Soren.

[38] Simpson stated Viren's pragmatism and "cross[ing] the line" came from being someone who "sees the end result, [and] knows he can [achieve it]", even through immoral actions.

[45][a] Michal Schick of Hypable praised Viren's role in the first season as an antagonist with "nuanced and real" morality and motives rather than as an "unambiguous villain".

[51] Nelson, writing for The Verge, appreciated the way the second season uses flashbacks and his intention to prevent further tragedy to juxtapose Viren's genuine love for Harrow with "terrible things [he does] with his dark magic".

[52] IGN's David Griffin also said the season's flashbacks effectively display the complexity of Viren's character and make the audience question his morality.

[53] Radulovic and Marshall said one of Viren's most compelling traits is his relatability, noting that while his relationship with his children—especially Claudia—does not absolve him, his desire to "leave a legacy behind for his children [is] an empathetic motivation to his drastic deeds" helps humanize him.

[55] The Daily Dot's Gavia Baker-Whitelaw described Viren's storyline as one of the best in the second season and called his relationship with Aaravos "intriguing".

[57] Nelson also reacted positively to the relationship between the two characters and the way Aaravos "preys on Viren's ambition and desperation to fulfill his own mysterious, malevolent goals".