"Power beckons, and who among us is strong enough to ignore its siren song?"
- – Neroon
During the Earth-Minbari War, Neroon fought against the humans and claims to have killed 50,000 during its course. He was the second in command under Shai Alyt Bramner, another member of the Star Riders. He was taught the Denn'bok, or Minbari fighting pike, by Durhan himself, one of the greatest generals and leaders of the Minbari his time.
In 2258, Shai Alyt Bramner died, and his passing was considered a great loss to the Minbari. Neroon was charged with parading Bramner's body through various sectors in a solemn vigil. One stop on the journey was Babylon 5. Here the body went missing, enraging Neroon and upsetting all the Minbari with on the station. Neroon insisted on helping Michael Garibaldi with the investigation, which including confronting a pak'ma'ra, well known as carrion eaters capable of consuming dead sentients. Neroon quickly grew impatient with Garibaldi's search, pressuring Sinclair. Neroon decided to slip into Sinclair's quarters, believing it would be the one place no one had searched, and in the dark Sinclair briefly fights him. Garibaldi arrives a moment later to separate them, and explains to Neroon Sinclair's quarters were searched first. Neroon was angered when Delenn finally admitted she had taken the body and had it cremated, per Bramner's wishes, which the Star Riders disrespected. Neroon threatens to make the matter public, but Delenn insists on keeping it quiet, or threatens that the Grey Council will dishonor and destroy the Star Riders. Neroon accepts the order, as well as her order to apologize privately to Sinclair. She promises him no one will blame the Star Riders for what happened. Neroon apologizes to Sinclair, who offers a personal message of high praise to Bramner, whom he opposed on the Battle of the Line. This is taken as a great gesture, and Neroon adopts a level of respect for Sinclair.
In 2259, he replaced Delenn on the Grey Council, upsetting the balance of three members of each caste. The warrior caste justified the decision by arguing it had been the warrior caste who died in the war, but it was the Religious Caste that stopped it. Neroon, angry over the truth to him of why the Earth-Minbari War ended, sent Delenn back to Babylon 5 "where she belonged."
The following year, after the Shadows had succeeded in sowing chaos across the galaxy; Neroon and the warriors in the Council continued their policy of isolation for the Minbari Federation. When Babylon 5 declared independence, however, Delenn disbanded the Council as Valen had prophesied would happen.
"A religious zealot propelled by prophecy into a position of military and political power? Always a bad idea."
- – Neroon, to Delenn
Not long after the Council is disbanded, Jeffrey Sinclair disappears, leaving the Rangers without a leader. Delenn is selected as the natural choice, and an official installation ceremony is planned to occur on Babylon 5. Neroon feared Delenn's ultimate intention in dissolving the Council and taking over the Rangers was to become the absolute ruler of the Minbari Federation. He traveled to B5 to stop her from becoming Entil'Zha of the Rangers. When he first arrives, he approaches her respectfully and asks she peacefully turn over control of the Rangers to the Warrior Caste. When she does not do so immediately, he vows to stop her meaning any means necessary. When Delenn refuses to alert Captain Sheridan about Neroon's presence, her aide Lennier asks Marcus Cole, himself a Ranger, to delay Neroon until after the installation ceremony. Marcus ignores Lennier's warning about confronting Neroon directly. He tracks down Neroon and invokes Denn-shah, a fight to the death using the Denn'bok, even though he knows he cannot possibly defeat Neroon due to Neroon's vast fighting experience in comparison to Marcus. After a brief but fierce battle, Neroon has Marcus at his mercy, asking him why he insisted on throwing his life away. Marcus, invoking the name of Valen, explains that he did it for Delenn, the One whom the Rangers will follow.
Neroon leaves Marcus alive and marches into the closing part of the ceremony. Casting aside his pike, he warns Delenn that there is blood between the two castes now. He acknowledges, however, that the Rangers will die for her in a way they never would for him or any other member of the warrior caste. He completes the last word of the ceremony before leaving. Later, he visits Marcus in the Medlab and explains that he "died" in the battle--his old self died when he realized how close he came to killing a fellow Minbari while a human had been ready to die for one. He and Marcus then share a friendly moment as fellow warriors.
Following the end of the Second Shadow War, the power vacuum that existed without the Grey Council ultimately leads to the Minbari Civil War. Delenn contacts Neroon on her way back to Minbar, asking him to meet with her aboard a Minbari cruiser. Neroon agreed, bringing a small contingent with him. Delenn appealed to him to join with her in stopping the Civil War before it escalates out of control. Both acknowledged their past differences but agreed that they both wanted what was best for their people. She warns him that if either caste surrenders to the other, it will tear their entire civilization apart. Neroon seemingly agrees to her request. Along the way back, one of his fellow warriors attacks him, believing he is betraying his caste, desiring them to surrender to the Religious Caste. Neroon suffers only minor injuries and is treated by Delenn's people. However, in the middle of the night, a few hours before they arrive home, Neroon leaves the ship in his own flyer, having stolen vital information that will allow the Warrior Caste to crush their opposition in the capital.
Or so it seemed. Neroon, aware of the tyrannical nature of Shai Alyt Shakiri, the one leading the Warrior Caste, had agreed to go along with Delenn's desperate plan to restore balance and peace. After a few more days of fighting in Yedor, Delenn announced that the Religious Caste was surrendering to the Warrior Caste. Neroon made the arrangements for the time and place (per Delenn's plans), inside the Temple of Varenni, a place where in the ancient times the ruling castes were selected by a device known as the Starfire Wheel. While being broadcast over the entire planet, Delenn surrenders, then demands that Shakiri step with her into the Starfire Wheel to determine if the Warrior Caste is indeed fit to rule. Shakiri refuses at first, until Neroon goads him. Once inside, he quickly panics and leaves, not willing to sacrifice his own life for his cause. Delenn remains inside, willing to die for her people--but Neroon (unaware she did not intend to step out once Shakiri fled) saves her and remains inside the circle. As the light and fire begins to overwhelm him, he professes that his heart was truly Religious Caste and the Minbari should listen to Delenn as well as expressing his admiration for her. He is then vaporized by the power of the Wheel.
Afterwards, when Delenn reorganizes the Grey Council, she leaves the leadership place empty in Neroon's memory.
- "All Alone in the Night"
- "Grey 17 Is Missing"
- Rumors, Bargains and Lies"
- Moments of Transition"