Thon

The early years of Thon's life are shrouded in mystery. He belonged to the Tchuukthai, a quadrupedal, beast-like alien species that originated from a planet located far within the Unknown Regions. The location of this planet was a closely guarded secret. The Tchuukthai were extremely secretive and reclusive, which meant that information about them and their homeworld was unreliable, especially during Thon's lifetime. Most members of galactic society considered the few Tchuukthai who ventured off their homeworld to be little more than savage beasts, until a Jedi Master, whose name has been lost to history, discovered their true intelligence. This Jedi befriended Thon on the Tchuukthai's planet and shared knowledge of the galaxy with him. Thon became fascinated by the wonders of the wider galaxy, and the Jedi Master eventually offered to teach him about the light side of the Force. Initially, Thon was hesitant to leave his planet, fearing that his species would be exploited by galactic criminals if their intelligence became known. However, the Jedi Master promised to keep the Tchuukthai's intelligence a secret and trained Thon in the ways of the Force. Thon eventually became a powerful Jedi, mastering many Force powers and becoming skilled in lightsaber combat.

Later, Thon, having completed his Force training, arrived on the Jedi world of Ossus. He revealed nothing about his origins or how he had acquired his powers, making him a subject of great interest to the Jedi Masters. Almost nothing was known about his species. The Republic Bureau of Xenology had labeled them "Wharl" due to the complete lack of information about the Tchuukthai. The Bureau repeatedly questioned Thon about his species, but eventually gave up after he consistently ignored them. Thon had mastered every power known to the Jedi and even taught the other Masters several powers that were previously unknown to them. When asked about his origins, Thon always responded, "It is better that you do not know—at least, not yet." The other Jedi accepted this explanation, but it only increased their curiosity about the reclusive Jedi Master.

Eventually, Thon became one of the most respected and advanced Jedi Masters of his time, alongside figures such as Odan-Urr, Vodo-Siosk Baas, Ood Bnar, and Arca Jeth. During his time on Ossus, Thon inherited the Jedi holocron that had belonged to Ood Bnar, an ancient Jedi Master who had lived for centuries and served as its gatekeeper. Bnar possessed extensive knowledge of the history of the Sith and the dark side of the Force, and he had provided the Jedi Order with the information they needed to defend against these threats for centuries. He created a holocron, which was passed down through the generations until it came into the possession of Master Arca, who then lent it to Thon.

Thon remained on Ossus for several years before leaving to find a more secluded location to train his students in peace. He wore no clothing and carried only a single item—an ancient lightsaber—as he traveled across the galaxy in his ship, guided solely by the Force. One day, his attention was drawn to a place beyond the reach of his ship's sensors, surrounded by dark side energies. Thon meditated on this presence as the Force guided his ship to the source of the energies. He eventually arrived in the Stenness system and journeyed to the planet Ambria, which was then known as Stenness.

Thon quickly realized that Ambria was radiating dark side energy and sought to find its origin. Ambria, a mineral-rich world that had once been a hub for miners, had never been fully colonized due to its barren and inhospitable environment. After much of its natural resources were depleted, the planet became the home of a Sith sorceress, whose name has been lost to time but was recorded in the archives of the Jedi Order on Ossus. Using her Sith powers, she constructed a great obelisk infused with the dark side. Once completed, she attempted to perform an ancient Sith ritual. However, the ritual proved too complex for her to execute correctly, and she inadvertently released a wave of dark side energy that eradicated the few sentient beings living on the planet, further damaged the atmosphere, and tainted the planet with dark side energies. The planet then became a focal point for the Sith during the fall of the Sith Empire, who eventually passed away, leaving malevolent spirits behind on Ambria. These energies and spirits remained on the planet for many centuries, eventually guiding Thon to Ambria.

Thon landed on the surface of the barren planet and was immediately ambushed by the Sith spirits, which he easily repelled with his superior knowledge of the Force. However, after much time and effort, Thon became thoroughly exhausted, and his ability to repel the attackers was diminishing. He devised a strategy to defeat the Sith. He swam into the middle of Lake Natth, the largest body of water on the planet. Upon reaching the center of the lake, Thon feigned giving in to the dark side, allowing the Sith energies to swarm around his limp body. He then cleverly used his remaining energy to use the Force to trap his adversaries in a web of light side energy before leaving the lake permanently. He named the lake "Natth," which means "cage" in the Tchuukthese language. The spirits, enraged at being trapped beneath the lake's waters, possessed and mutated the local life forms, creating dark side monsters known as hssiss. With the exception of Lake Natth, Ambria was finally cleansed of the dark side.

While exploring the planet, Thon discovered a meditative canyon situated in the Tiernvael Mountains in the northern region of the planet. This area was even more desolate than the rest of the planet, with minimal rainfall and no wildlife. This was largely due to its proximity to the Sith obelisk built by the long-dead Sorceress, although unusual weather patterns also contributed. While the area occasionally experienced brief periods of calmness, frequent sandstorms made travel nearly impossible. During one such storm, Thon sought shelter in the canyon and discovered that one particular wall had an unusually powerful connection to the Force. He entered a meditative trance to recover from the injuries he had sustained during the storm and found that the wall made him feel at ease, oblivious to the chaos around him. He also noticed a collection of transparent crystals that, although they had no impact on the Force, could be used as a focal point during meditation. The storm eventually subsided, and although Thon left, he remembered the location of the canyon. He returned there for many years whenever he needed spiritual solace.

Thon established a small training center near Lake Natth and arranged for various animal species to be transported to Ambria from different worlds throughout the galaxy in an effort to restore the desolate planet. For over a decade, Thon trained several students on Ambria, including a young Vultan named Oss Wilum. Wilum had previously been a student of Jedi Master Garnoo, but when the Neti Master died, Wilum was left without a tutor. During one of his rare trips off-world, Thon recognized Wilum's Force potential and brought him to Ambria to complete his training. After five years of learning, Wilum completed his apprenticeship and surpassed Thon's expectations. The Tchuukthai was surprised by how quickly his apprentice had progressed, considering how late in life he had begun his training. Thon knew that Wilum was ready to join the ranks of the Jedi Knights and that Arca Jeth needed more Jedi to assist him on Onderon, where the Naddist cult was in revolt. He also arranged for another Jedi Master, Chamma, to send a young Human named Andur Sunrider to Ambria to continue his training under the Tchuukthai.

Sunrider had learned all that Chamma believed he could teach him, so the ancient Jedi decided to send him to Thon in the Stenness system. Andur was scheduled to arrive on the planet in his ship, the Lightside Explorer, along with his wife Nomi, their infant daughter Vima, and their droid, A-3DO. However, on their way to Thon's compound, they were ambushed by thugs sent by Bogga the Hutt, the local crime lord, to steal Andur's Adegan crystals, which were intended as Master Chamma's gift to Thon in gratitude for training Andur. During the ambush, Andur was killed, forcing his wife Nomi to retaliate and kill the assassins with her late husband's lightsaber. After his death, Andur appeared to Nomi as a Force ghost and urged her to deliver the crystals to Thon, assuring her that the old Tchuukthai Master would help her decide what to do next. Nomi honored her husband's wish and continued toward Thon's home. Oss Wilum had not yet left for Onderon, so he accompanied Thon to meet Nomi, whom they saw standing on a hill overlooking the Tchuukthai's house.

Thon led Oss toward Nomi, who initially mistook the Vultan Padawan for the Jedi Master, believing Thon to be a simple beast. Thon did not correct this misinterpretation, remaining silent and acting as if he were an unintelligent animal. Thon and his apprentice led the young woman to the house, providing food for her and her child. As Sunrider began to recount her ordeal, they were interrupted by the arrival of Bogga and his cronies on his sail barge. The Hutt, who had always harbored a deep hatred for Thon, was determined to steal Nomi's valuable Adegan crystals. Thon watched as Wilum attempted to engage the Hutt's men in combat, but the young Jedi was outnumbered and soon captured. Thon then acted, leaping at the men and using the Force to knock them back. Bogga, realizing they were outmatched, ordered a retreat, but he did not abandon his hopes of acquiring the crystals. It was then that Nomi finally realized that the beast was Thon and that he would be teaching her the ways of the Force.

For the next few months, Thon remained silent to his new pupil, allowing her time to grieve Andur's death and to decide the future direction of her life. Nomi began to doubt Thon and spent much time contemplating his unusual teaching methods. While Thon was away, Nomi unknowingly used the Force to protect her daughter Vima from the hssiss that inhabited Lake Natth. In reality, Nomi was using basic battle meditation, although she did not realize it at the time. Although the hssiss were defeated, the malevolent spirits in the lake reached out to Nomi and told her she was going to die. Nomi fled the lake, still harboring doubts about Thon and questioning why she was on this savage world.

Upon Nomi's return, Thon fully recognized her potential and knew that she would one day become a great Jedi Master. Thon was also aware of the major conflicts that would occur in the galaxy and the role Nomi would play in them. It was then that he decided to begin her training. Oss Wilum had not yet left for Onderon, and Thon met with Tott Doneeta, a Twi'lek apprentice of Arca Jeth, who had recently arrived on Ambria to request assistance from the Tchuukthai Master. With Thon's permission, Wilum accompanied Doneeta back to Master Arca on Onderon, finally leaving Thon alone with Nomi Sunrider to begin her training. He told his new apprentice that she would use her Adegan crystals to build a lightsaber, but Sunrider was reluctant to ever use such a weapon again. She had only killed with Andur's saber hesitantly and was unwilling to do so again. Thon explained that her previous experience with the weapon had been in self-defense and that she had already demonstrated great skill with the blade. The red-haired Human insisted that Thon did not use a lightsaber and that she would only accept his tutelage if she did not have to use one. Thon agreed, although he knew she would eventually change her mind.

Thon decided to take Sunrider to the Meditative Canyon, where her training would begin. He explained to her that it was not enough for a Jedi to simply know the light; they had to feel the tension between light and dark, both within themselves and in the wider universe. He told her that the dark side challenged them, forcing them to reach beyond their limits, as Nomi had done when she rescued her child. They stopped at Lake Natth, but Nomi, concerned for her child's safety, wanted to go elsewhere. Thon complied and took Nomi and Vima to the edge of the great canyon where he regularly meditated. Thon then showed Sunrider his Jedi Holocron, whose gatekeeper was the ancient Neti Jedi Master Ood Bnar. The tree-like man from Myrkr told them about those who had fallen to the dark side and that a great conflict between the Jedi and the worshipers of the dark side would occur within Nomi's lifetime. As he pointed at the young apprentice and declared that she would play a pivotal role in the war, Vima became frightened, and Thon deactivated the holocron. He told Nomi to take his lightsaber, which he had used during his Jedi training. Nomi was frightened by what Bnar's holocron had revealed and wanted to leave the planet and start a new life with her daughter Vima. However, Thon knew what she was thinking and told her that there was no going back for Nomi Sunrider—there was only moving forward or succumbing to darkness.

Meanwhile, Bogga remained determined to acquire the Adegan crystals and rid "his" system of Thon, who had become a persistent thorn in his side. A local pirate named Finhead Stonebone had incurred Bogga's wrath after raiding an Ithullan ore hauler. The Hutt ordered him to kill Thon as restitution, or he would be executed himself. When Stonebone refused, knowing that attempting to kill a Jedi Master would be suicidal, Bogga had his first mate killed by the Hutt's pet hssiss, forcing Stonebone to reconsider.

Thon and Nomi were returning to the training compound when Stonebone and his motley crew, along with an entourage of Bogga's rough enforcers led by the gangster Gudb, arrived on Ambria in armored skiffs and began firing rockets at the building. While Thon was able to use the Force to deflect the cannon rounds, he instructed Nomi to take up the lightsaber so they could fight the pirates together. Nomi, however, was adamant that she would never touch the weapon again and apologized to Thon for letting him down. The salvos soon broke through Thon's defenses, forcing the Jedi Master to charge the hovering skiffs, terrifying Nomi. Thon attempted to persuade her to use her battle meditation if she refused to wield the lightsaber, but she refused again, stating that he was the Jedi Master and that she had to rush Vima to safety. Thon allowed her to do so, claiming that if his apprentice had no power, neither did he. He surrendered himself to Stonebone's gang, allowing them to fit him with Mandalorian manacles and lead him toward their skiffs. Using the Force, Thon telepathically urged Sunrider to use her battle meditation, but she resisted acknowledging its existence. Finhead Stonebone's men then prepared to lift Thon onto the skiffs.

The pirates entered Thon's compound, searching for the Adegan crystals, while Nomi contemplated the loss of another Jedi. Soon, one of Bogga's enforcers, who had been sent by the Hutt to work with Stonebone's crew, discovered the crystals in Thon's hut. This sparked a conflict within the group of alien criminals, and a massive fight erupted over who would present the valuable crystals to Great Bogga. Nomi, who had decided to use her battle meditation, influenced the gangsters' thoughts. While the thugs fought each other, Nomi took hold of the lightsaber and finally accepted that she had to use it. She freed Thon and charged at the raiders, aided by the great Tchuukthai Master, who unleashed bursts of powerful, concentrated Force energy at them. Finally, through the combined efforts of Thon and his apprentice, Bogga's men were defeated, and Stonebone retreated from Ambria. Nomi Sunrider had finally accepted her destiny as a Jedi, and Thon began to teach her everything he knew.

After a period of instruction where Thon imparted all his wisdom to his young student, the venerable Tchuukthai decided to escort Nomi to Ossus. This was done so she could further her Jedi training under the tutelage of Krevaaki Jedi Master Vodo-Siosk Baas. Vodo-Siosk Baas would begin by guiding Nomi in constructing her own lightsaber, utilizing the Adegan crystals that Chamma had originally intended for Thon. Nomi immediately felt at home on the Jedi training planet, remarking on its serenity and peacefulness. Thon then accompanied Nomi and Vima to meet Master Vodo, who was concurrently instructing the young Jedi Knights Dace Diath, Shoaneb Culu, and Qrrrl Toq in the craft of lightsaber construction. Upon their introduction, Vodo, echoing the sentiments of Thon and Ood Bnar, recognized Nomi's profound connection to the Force, expressing his belief that she possessed the potential to become a remarkable Jedi.

Thon remained with Nomi on Ossus for the duration of her training under Vodo, which lasted several months. Soon, she was prepared to embark with the other young Jedi Knights. Prior to Sunrider's mission to Onderon, Thon escorted her to the galactic capital of Coruscant to confer with the Republic Ministry of Defense. Speaking in his native Tchuukthese, Thon requested that his apprentice translate his plea for assistance from the Galactic Senate to aid the Jedi who were under duress on Onderon. Thon reminded the senators of the Jedi Order's long-standing alliance with the Republic, emphasizing that reciprocal support was now essential. When the senators exhibited reluctance, Thon cautioned them that the Naddists' conquest of Onderon would inevitably lead to the spread of their dark influence throughout the galaxy. This decisive statement persuaded the Defense Ministry to deploy the full might of the Republic Navy in support of the Jedi. Similar to Thon's previous student Oss Wilum, Nomi was assigned to assist Arca in addressing the Freedon Nadd Uprising on Onderon. Following Nomi's departure, Thon returned to Ambria, finding himself alone once more.

In the year 3997 BBY, circumstances compelled Thon to leave Ambria again. The Jedi leaders had convened a great convocation of the Order to address the threat posed by the Sith-inspired Krath, a group formed by members of Empress Teta's aristocracy in the aftermath of the Naddist Uprising. The Krath sorcerers had recently launched a series of attacks against the Republic, and their escalating dark-side influence demanded the collective attention of all Jedi. The meeting was held on the planet Deneba, presided over by Master Odan-Urr himself. Thon's former apprentice found herself at the center of attention, as she and Ulic Qel-Droma had spearheaded Republic forces in battle against the Krath. Unbeknownst to the Order, the Krath were preparing another assault. Dark-side agents had reprogrammed the servant droids used by the Jedi Masters to attack their owners on command, and a ship loaded with combat droids was en route to Deneba.

As the debate regarding the appropriate response to the Krath continued, the Krath initiated their attack. War droids descended upon the assembly just as the Jedi's own droids turned against them. The Jedi fought with valor, employing Arca Jeth's technique of disabling the automatons' internal mechanisms using the Force. Ultimately, the Jedi prevailed, but at a significant cost—Master Arca himself perished before the battle concluded. In the aftermath of this disaster, Thon, along with many of the surviving Jedi Masters, returned to Ossus while their students embarked on missions to address the Krath threat. Against the counsel of several Masters, including Thon, Ulic Qel-Droma ventured to the Krath on a mission to infiltrate their ranks and dismantle their reign of terror from within.

After several months passed without any communication from the undercover Jedi, Nomi Sunrider, accompanied by Cay Qel-Droma and Tott Doneeta, traveled to the Krath capital of Cinnagar to establish contact with Ulic. However, their mission was unsuccessful, as they discovered that Ulic had aligned himself with the Krath, even going so far as to capture Nomi and order her execution. After narrowly escaping Cinnagar, the three Jedi returned to Ossus to propose a new plan. Thon expressed his reservations about Qel-Droma, suggesting that the young Knight might be beyond their help. He believed that Ulic had made his own choice and might eventually recognize his error without their intervention. Nevertheless, Thon insisted that they allow Ulic to determine his own path, consenting to allow his former student to lead another attempt to rescue her friend. However, the plan failed once again, as Ulic Qel-Droma reaffirmed his commitment to the Krath, subsequently becoming one of the new Dark Lords of the Sith alongside Exar Kun, a former student of Vodo-Siosk Baas.

Thon returned to Ambria and remained there as the war with the Sith escalated. The Krath, under the leadership of Qel-Droma, launched attacks on the Republic and the Jedi. Their forces were bolstered by the armies of Mandalore the Indomitable. Nomi Sunrider, accompanied by Vodo-Siosk Baas and a group of other Jedi, attempted to persuade the Republic Senate to allow the Jedi to handle these matters, but their efforts were in vain. The Krath attacked Coruscant itself, led by Ulic Qel-Droma. The Jedi and the Republic emerged victorious when Qel-Droma was betrayed and abandoned by his lieutenant and lover, the Tetan sorceress Aleema Keto, who sought to seize control of the Krath. The traitor was captured due to his underlings' treachery and was scheduled to stand trial for his actions.

Meanwhile, Exar Kun was recruiting young Jedi to his cause, which he deceptively presented as a new Jedi Order. He claimed that its teachings were supplemented by knowledge that the Jedi Masters had withheld from their students—Sith knowledge. After murdering Master Odan-Urr to obtain a Sith holocron that the Jedi historian had been safeguarding, he used the artifact as "proof" of the hidden knowledge. He promised that this knowledge would usher in a new golden age for the Jedi. Among the young Jedi Knights who accompanied Kun from Ossus to his base on Yavin 4 was Thon's former apprentice, Oss Wilum. Although Wilum harbored more doubts than the others regarding Kun's knowledge and intentions, the new Dark Lord of the Sith used dark-side magic to enthrall the group, possessing them with Sith spirits.

Ulic Qel-Droma stood trial before the Senate, and Nomi Sunrider, along with Ulic's brother Cay and the Cathar Jedi Sylvar, attended. The proceedings took a disastrous turn when Qel-Droma, instead of atoning for his crimes, denounced the Republic and the Jedi. Exar Kun intervened to rescue Ulic from the tribunal, murdering the Supreme Chancellor of the Republic and slaying Master Vodo in the process. Nomi Sunrider, disheartened, sought solace with Thon on Ambria, accompanied by Sylvar.

Another of Thon's former students, Oss Wilum, now the unwitting servant of Exar Kun, was also planning to visit his master. Accompanied by Crado, Sylvar's mate and another of Kun's minions, Oss was dispatched to Ambria to assassinate Thon as part of a larger plot orchestrated by Kun to eliminate the Jedi Masters of the Order. As Nomi Sunrider, her daughter Vima, and Sylvar arrived at Thon's residence, Oss Wilum and Crado were at Lake Natth, preparing to carry out their mission. The pair summoned the monstrous hssiss from the lake using Sith magic and set off toward their target.

Sensing the disturbance, the three Jedi hastened to intercept the attack. Nomi and Sylvar engaged the hssiss with their lightsabers, while Thon charged into the fray, attacking the beasts with his teeth and claws. The hssiss were nearly defeated when Sunrider employed her skills in battle meditation to distract them, allowing Thon to deliver the final blows. Sylvar and Thon swiftly turned their attention to Oss Wilum, subduing him and freeing him from his Sith-induced trance. After a brief confrontation in which Sylvar condemned her mate for his actions, Crado fled, and the three Jedi assisted the injured Wilum into the house. Thon succeeded in restoring his fallen student to the light, but the Tchuukthai Master never fully recovered from the pain of betrayal. He feared for the other Masters, only to later learn that his fears had been realized: Kun's minions had succeeded in assassinating all of their Masters, and Thon was the sole survivor.

Thon and the three Jedi, along with young Vima, returned to Ossus to consult with the Order regarding the escalating crisis. As Thon and Nomi Sunrider discussed the fall of Ulic Qel-Droma and the murders of the Jedi Masters with other Jedi, Tott Doneeta burst in with urgent news: the Sith were attacking again. The space station known as Kemplex Nine, situated in the Cron Cluster of the Auril sector, was under siege by a Sith vessel of ancient origins. Thon advised caution, noting that the station itself was not a significant military target and suspecting that the Sith were staging a diversion. Given Ossus's proximity and greater strategic importance, it would be a more likely target. Consequently, the Jedi decided to divide their forces. Jedi Shadows Dace Diath, Qrrrl Toq, and Shoaneb Culu volunteered to lead a fleet to counterattack at Kemplex, while Thon and the remaining Jedi stayed on Ossus to safeguard the library world.

The attack did indeed prove to be a feint by the Sith, but not in the way the Jedi had anticipated. The ancient Sith battleship, commanded by Crado and Aleema Keto, lured the Jedi and Republic forces into the Cron Cluster. There, Aleema used Sith magic to extract the core of one of the cluster's stars, annihilating the Jedi fleet. The resulting reaction spiraled out of control, causing an implosion of the core and a subsequent supernova, killing Crado and Aleema and unleashing a massive stellar shockwave. Ossus lay directly in the path of the explosion and had minimal time remaining before the devastation reached it.

As the shockwave approached the planet, the Jedi raced to evacuate all living beings and as many precious records and artifacts as possible. As the remaining inhabitants of Ossus hastily made their choices about what to take or leave behind, Thon and his companions were overcome with grief at the planet's impending destruction. As they headed for their transports, Cay Qel-Droma sensed a presence above: Ulic was arriving on the planet, accompanied by Sith and Mandalorian forces that Exar Kun had brought to plunder Ossus before its destruction. Cay flew off in the Nebulon Ranger to confront his brother.

Exar Kun landed and immediately made his way to the libraries to seize as much valuable Jedi information as possible. He entered a chamber where Ood Bnar was working to place artifacts and scrolls in a shielded vault before evacuating, and the two engaged in battle. As Kun's Sith Massassi warriors came to their master's aid, Bnar realized that he could not defeat them. He then forced himself into his species' metamorphosis, transforming himself into a stout tree to prevent Exar Kun from taking the relics. However, this action rendered him immobile, binding his fate to that of the planet.

As the evacuation continued, Thon noticed the attackers' ships in the air. Among them were Ulic Qel-Droma's vessel and the Nebulon Ranger, piloted by Cay. The ships were plummeting from the sky. Tott Doneeta and Nomi Sunrider sped off to assist them, leaving Vima in Thon's care. Arriving at the crash site, Nomi witnessed a tragic scene: Ulic had just killed his own brother. To prevent Qel-Droma from ever again wielding the dark side, Nomi used a rare ability to sever Qel-Droma's connection to the Force completely.

Thon, Vima, and Oss Wilum soon arrived and learned of the events that had transpired. The Tchuukthai Master instructed everyone to board their ships and then departed on a final errand on Ossus—to bid farewell to Ood Bnar. Thon found Bnar in tree-form atop the shielded vault and expressed his sorrow for Ood's sacrifice. Bnar reassured him that he had accomplished his goal and might even survive the impending cataclysm. The two exchanged their goodbyes, and Thon returned to his ship, leaving Ossus behind forever. The shockwave arrived shortly thereafter, completely obliterating the planet.

In an opportunity to partially atone for his actions, Ulic Qel-Droma led a Jedi and Republic fleet to Exar Kun's base on Yavin 4. Thon accompanied the fleet in his personal transport. Knowing that he could no longer defeat the forces arrayed against him without his allies, Kun employed Sith magic to secure another escape. Drawing upon the life-force of the entire Massassi race on the moon, he freed his spirit from his physical body, achieving a form of immortality. Realizing that he remained a threat even without a corporeal form, Nomi Sunrider used the Force to bind Kun's spirit to the planet, preventing him from escaping into the wider galaxy. The Sith War had ended, and the Jedi had emerged victorious, but at a tremendous cost.

Following the events of the Great Sith War, the Republic, and the Jedi Order with it, gradually recovered. Nomi Sunrider, Thon's former apprentice, gained widespread recognition and was appointed head of the Jedi Order. A decade after the war's conclusion, it was decided that a conclave would be held on Exis Station in the Teedio system, as the Order had not convened in significant numbers since the grand convocation on Deneba during the Krath crisis. Upon arriving at the station, Thon was delighted to see Vima Sunrider, now a young teenager, who had accompanied her mother to the conference. He was also greeted by Sylvar, who had become more embittered in the years since the war despite her heroic status, but Thon was nonetheless pleased to see her.

The conclave commenced, led by Nomi Sunrider, who spoke of the horrors of the war and the healing that had occurred since. As his dear friend and former student spoke, Thon observed that she had become a remarkable Jedi, and the rest of the Order held her in high regard. However, the speech was abruptly interrupted when Nomi, Sylvar, and Thon sensed a disturbance in the Force. It was Vima; she was in danger.

The teenage girl, bored with the conclave and frustrated by her mother's neglect of her Jedi instruction, had slipped away and stolen one of the ion mining ships in the station's hangars. She quickly lost control of the vessel as it became trapped in one of the nearby star's magnetic loops. The assembled Jedi were largely helpless as Vima ejected from her vehicle before it could crash into the star. However, she was not out of danger, as the miners' foreman refused to risk additional ships to retrieve her escape pod before it, too, might fall into the inferno. Vima was rescued when Tott Doneeta, arriving late to the conclave, grappled the escape pod with his ship.

With Vima safe and back on the station, the meeting resumed. Sylvar spoke next, addressing the topic of Ulic Qel-Droma. The former Sith Lord had been living in self-imposed exile since the Sith War, although he remained technically a war criminal. Severed from the Force, he wandered from planet to planet, seeking a place to live out his days in solitude. Sylvar disagreed with this, holding Qel-Droma accountable for the atrocities of the war and demanding that he be punished for his crimes rather than allowed to roam free.

The convocation concluded on this note. Sylvar departed with Tott Doneeta for Ryloth, while Thon remained on Exis Station with Nomi Sunrider. Yet again, Vima was nowhere to be found. The girl had stowed away aboard a ship and traveled to the frozen planet Rhen Var, where Ulic Qel-Droma was living in seclusion. Having fewer negative memories of the man than her contemporaries, she hoped to persuade Ulic to train her in the Jedi arts. After a thorough search of Exis Station, Thon informed Nomi that her daughter was missing and likely no longer on the station.

Nomi resolved to find her daughter and traveled to Rhen Var alone, but not before the girl had received significant training from Qel-Droma. Sylvar was also on the planet, having arrived with the spacer Hoggon, who had transported first Ulic and then Vima to Rhen Var. As Nomi conversed with her daughter, Sylvar confronted Qel-Droma, and the two engaged in combat. In the end, although Sylvar refused to kill Qel-Droma when he was unarmed and unwilling to fight back, the fallen Jedi was killed by a blaster bolt fired by Hoggon, who sought to secure a place in history for himself. The three Jedi departed Rhen Var, and Nomi Sunrider took Vima as her apprentice to complete the girl's training.

Thon's name, and the stories associated with it, remained well-known for millennia. He featured in the tales of Ulic Qel-Droma and Nomi Sunrider contained within the Tedryn holocron and recounted by Bodo Baas, a descendant of Thon's contemporary, Vodo-Siosk Baas. His Force abilities were celebrated by Beldorion, a Hutt Jedi who admired his skills. Tionne Solusar, a Jedi historian who lived thousands of years after the Sith War, composed a ballad honoring Thon's most famous apprentice. Solusar, having dedicated her life to studying legendary Jedi, possessed extensive knowledge of the individuals Thon knew during his lifetime.

Thon's efforts on Ambria eventually bore fruit, and over the course of centuries, the barren planet began to recover. However, the dark-side spirits contained within Lake Natth continued to plague the planet indefinitely. In later eras, the meditative canyon discovered by Thon became a sanctuary for Jedi seeking refuge, and during Palpatine's Great Jedi Purges, many Jedi used the canyon as a hideout.

Despite his renown as a Jedi Master and his role in training numerous students, Thon led a simple life on Ambria, residing in a modest dwelling near Lake Natth. During Oss Wilum's training, the two Jedi tended to a herd of staga native to the planet. Although Thon possessed a lightsaber, his only possession when he arrived on Ambria, and even a set of Jedi robes, he was not known to travel with such trappings of the Jedi for much of his life, which he spent in seclusion with his students.

The Tchuukthai typically communicated in brief bursts, often incorporating phrases from his native language. However, he was capable of speaking at length on important matters and was known to be quite eloquent on occasion. He often expressed himself and imparted lessons in a profound manner. When Nomi Sunrider first arrived on Ossus, Thon feigned being a simple beast under Wilum's care, and after she discovered his true identity, he refrained from speaking to her for months, allowing her to grieve her husband's death. However, Thon could also be a warm and compassionate being. He was frequently involved in the upbringing, care, and initial Jedi training of Vima Sunrider during her childhood and even expressed a desire for a hug when they reunited on Exis Station. Conversely, when the situation demanded it, he adopted a firm stance. When the possibility of rescuing Ulic Qel-Droma from the Krath and restoring him to the light was discussed, Thon opposed the idea, suggesting that Qel-Droma should learn from his mistakes without Jedi intervention. Thon was not as detached as Jedi of later eras. When his friend and colleague Ood Bnar essentially sacrificed himself to protect Jedi knowledge from Exar Kun, Thon made sure to visit him before leaving Ossus, expressing both sadness and respect for the Neti Master's decision.

As a Tchuukthai, Thon possessed significant natural defenses. He was large and muscular, easily capable of carrying adult humanoids on his back. A bony frill around his neckline, armor plating on his back, hornlike projections from his jaws, and spikes protruding from his shoulders provided additional protection. Each of Thon's four legs ended in a set of sharp, strong claws, ideal for slashing. Furthermore, the Tchuukthai had powerful jaws filled with long, sharp teeth, which he used to great effect against the hssiss of Lake Natth.

When Thon initially stood before the Jedi Masters on Ossus, he already held a substantial understanding of Force abilities, surpassing even the Masters' knowledge in some areas. By the time Nomi Sunrider became his apprentice, Thon controlled a vast array of Force techniques. He demonstrated telepathic abilities by communicating with Nomi, after allowing his own capture, instructing her to employ battle meditation through the Force. While the Tchuukthai himself possessed battle meditation skills, Vodo-Siosk Baas considered Arca Jeth more proficient in this area. Furthermore, Thon escorted Nomi Sunrider to Ossus so Odan-Urr, who had a deeper understanding of battle meditation than he did, could improve her skills. Thon held the rank of Jedi Weapon Master, and although he could use a lightsaber, he directed Nomi to Vodo-Siosk Baas for guidance when she needed to construct her own weapon. Upon his arrival on Ambria, the Jedi Master initially found it easy to overcome the dark side spirits present. When exhaustion set in, he cleverly feigned weakness to draw them closer. He then used his significant capacity to channel light-side energy to completely trap the Sith apparitions. In addition, when Bogga the Hutt's henchmen launched an assault on Nomi and Oss Wilum, Thon unleashed powerful waves of Force energy to incapacitate them. Later, as Finhead Stonebone and his crew attacked Thon's residence from their skiffs, the Master deflected their projectiles using a Force energy barrier. It was later said that the Tchuukthai had the power to create light itself using the Force.

Centuries after their passing, both Thon and Nomi remained recognized as among the most formidable Jedi Masters of all time; indeed, the Hutt Jedi Beldorion appeared to regard them, along with Grand Master Yoda, as possessing unmatched mastery of the light side of the Force.

Tom Veitch, the writer, conceived the character Thon, who was initially referenced in the notes at the conclusion of the Star Wars: Dark Empire comic book series. Thon's first appearance was in Tales of the Jedi 3. He continued to appear in later issues of the Tales of the Jedi series, where Veitch, along with Kevin J. Anderson, further explored his character. Drew Karpyshyn, the author, mentions Thon in connection with Ambria in Darth Bane: Dynasty of Evil, the third book in the Darth Bane Trilogy. Thon receives only one direct mention in a novel set during the New Republic era, although Nomi Sunrider and "her Master" are mentioned in several others. Thon is briefly mentioned in the video game Star Wars: Knights of the Old Republic II: The Sith Lords, where the player can find a Jedi robe that supposedly belonged to the Tchuukthai master.