Vul Isen

Born more than a century after the Battle of Yavin, Vul Isen was a male Givin with Force-sensitivity. His birth occurred on Korriban, a planet serving as a stronghold for the One Sith. He was initiated into the One Sith alongside many other Sith who were also born on that world. However, Isen's expertise lay not in the realm of combat but rather in the field of science. As a result, he was not bestowed with the title of Darth, an honor reserved for the most skilled warriors within the One Sith. This distinction led to him being viewed with disdain by those who considered such Sith to be of lesser importance than their warrior counterparts. After his departure from Korriban, Isen refrained from carrying a lightsaber or donning the dark robes commonly worn by Sith warriors. Instead, he opted for a uniform resembling that worn by the Sith's military officers. Isen developed extensive knowledge and skill in his chosen domain, becoming an expert in the extermination or pacification of species that defied Sith rule. He engineered various destructive organisms capable of eradicating vast populations and transforming planets into swamps. However, he lamented the limited opportunities he had to properly test many of these creations.

Unlike the warriors who held him in low regard, Isen did not blindly adhere to the commands of the One Sith's leader, Darth Krayt. He felt no hesitation in questioning orders that seemed illogical to him, believing that a scientist's duty was to question everything. In 137 ABY, Krayt initiated the Genocide of Mon Calamari, ordering the execution or enslavement of all members of the Mon Calamari species on the planet Dac as punishment for their opposition to Krayt's Empire. Following the Massacre of New Coral City, many Mon Calamari sought refuge in the depths of the planet's oceans. Isen was tasked with utilizing his knowledge to expedite their elimination. Darth Azard, a Quarren Sith Lord, was stationed on Dac to oversee the extermination, and Isen reported directly to him.

Because Krayt's directive was to eliminate only the Mon Calamari and not the Quarren or any other native species of Dac, Isen was prohibited from releasing experimental viral organisms that would eradicate all life on the world. Consequently, the Givin consulted with several other high-ranking Sith to determine the most effective method of accelerating the process while ensuring that only the Mon Calamari were targeted. Darth Maladi, Krayt's chief scientist and torturer, offered no assistance, refusing to share her knowledge with him. Darth Wyyrlok, Krayt's most trusted advisor, suggested that Isen delve into ancient Sith lore and explore the possibility of adapting a Leviathan—an alchemically bioengineered Sithspawn created by Dark Jedi predating the Sith—for use in the sea. The resulting creature would be capable of eliminating the remaining Mon Calamari on Dac. Although semi-sentient, the Leviathan would absorb the life energies of its victims, becoming sentient and developing a Mon Calamari-like mindset, enabling it to better locate their hiding places. Isen dedicated weeks to engineering the creature in the expansive, underwater Soheras Trench, accessing the trench via an Imperial Aquatic Terrain Armored Transport, until the first Sea Leviathan was complete—requiring only a spark of the Force to awaken it.

Isen and Darth Azard journeyed together to the trench in a transport. Azard, one of those who believed that members of the One Sith who had not earned the Darth title were inferior, resented Isen's lack of complete obedience to Krayt's rule. During the transport, Isen attempted to initiate a conversation, expressing his desire to simply eradicate the entire world. Upon reaching the edge of the abyss, Isen and Azard jointly used the Force to awaken the creature, imprinting their minds and wills upon it and providing it with its directives. The first Sea Leviathan emerged from its slumber and immediately targeted a nearby enclosure of enslaved Mon Calamari, consuming their life energies. Isen explained the process of absorbing life forces, but Azard expressed concerns that the Leviathan might begin to think too much like a Mon Calamari and turn against the Imperials. Isen reassured him that this would not occur and managed to allay Azard's fears.

Darth Azard had already identified a target for the Sea Leviathan. Earlier that day, an Imperial Acklay Battle Fortress, the Sea Lion, had been attacked and disabled by a group of Mon Calamari Rangers, who were part of the resistance against the Empire on Dac, while tracking a group of refugees. Azard ordered Isen to direct the beast toward the refugees' location, with the aim of drawing out the Rangers and defeating them in one swift strike. Isen was impressed with Azard's plan and immediately began to implement it.

The Leviathan, accompanied by Isen and Azard in their transport, soon encountered two Mon Calamari Rangers piloting underwater Krakana fighters. The Mon Calamari attempted to evade the creature, but Isen's shuttle managed to damage one that had escaped the Leviathan's reach. The creature subsequently absorbed the life energies of the damaged ship's occupant, but one Krakana managed to escape, and its pilot sped back to her comrades in the Rangers' base. Isen ordered his gunners to allow the Mon Calamari to escape unhindered, so that she could inform the Rangers that the Imperials were coming for them. Isen believed that a Mon Calamari defeat was inevitable, but he felt it would be easier to eliminate them if they congregated in the same locations, rather than having to hunt them down individually. Isen informed Azard that he preferred breaking the will of a species, sparking a minor conflict between the two, which soon subsided.

The Leviathan followed the Mon Calamari's trail toward the Rangers' base, with the Imperial shuttle in tow. Isen grew increasingly agitated during the long journey, repeatedly questioning Azard as to whether they had arrived at their destination. The Quarren became impatient with the repetitive questioning and made his displeasure clear to Isen. Eventually, they reached the base, and swarms of Krakana emerged to confront them. The Mon Calamari avoided the Leviathan and instead targeted the shuttle, hoping that destroying it would halt the creature's attacks. The shuttle's shields withstood the Krakanas' plasma weapons, and since the Krakana were built for speed and lacked shielding of their own, Isen considered the Mon Calamari's tactics foolish.

Azard ordered the gunners to eliminate all of the Mon Calamari, and the transport began firing blaster fire in all directions. Although the Leviathan targeted escaping refugees, the Rangers remained steadfast in their task, searching for a weakness in the shuttle's armor. However, the situation turned against the Sith when the Rangers' ally, Imperial Knight Treis Sinde, arrived with numerous devilsquids, which swarmed around the Leviathan and attacked. Azard devised a plan: the shuttle would deploy its complement of Shark fighters to engage the Krakana, while he would deal with the devilsquids. Although the shields had to be lowered to launch the Sharks, Azard was confident that concentrating fire on the launch area would repel the Krakana.

Azard's assessment proved incorrect, as a lone Mon Calamari ranger drove at the shuttle, committing suicide by colliding with the Imperial vessel. Isen's shuttle was crippled, and the bridge area detached from the rest of the vessel, which sank to the sea floor. Isen escaped with minor injuries, but Azard was less fortunate and became pinned to his chair. Using the Quarren's lightsaber, Isen freed him and shattered one of the vessel's windows with the Force to create an escape route. Azard was surprised that Isen had rescued him, but the Givin remarked that they were both members of the One Sith and that Krayt would have wanted him to do so. The two then swam upward and away from the wreckage. Isen's creation, the Leviathan, was ultimately defeated by Sinde and the Mon Calamari Rangers.

Sometime later, Lord Azard and Vul Isen received a holographic transmission from Darth Wyyrlok, who had seized control of the Empire and the One Sith in the name of Darth Krayt. Lord Wyyrlok informed Azard and Isen that Emperor Krayt no longer wished to expend Imperial resources on the systematic extermination of the Mon Calamari and ordered Isen to execute the Final Protocol: the eradication of all life on Dac. Pleased with the prospect of continuing his work elsewhere, Isen infected Dac's oceans with viral spores, which would be carried by oceanic currents and kill every life form on the planet within a week. Three days later, Dac's oceans were covered with the bodies of the dead. Isen's actions resulted in the deaths of over eighty percent of the planet's population and would have led to total extermination if not for the intervention of the Galactic Alliance Remnant and an evacuation fleet of civilian volunteers.

Following the genocide, Isen earned the title Butcher of Dac for his atrocities on Dac. Cade Skywalker, now engaged in a personal vendetta against the One Sith, led a team consisting of Jariah Syn, Deliah Blue, and Wolf Sazen to Daluuj to locate and assassinate Isen. This mission was based on intelligence provided by Naxy Screeger. A group of Sith Lords rushed out to intercept the team, and while Syn and Blue infiltrated the facility to find Isen and plant explosives, Skywalker and Sazen engaged the Sith in combat. Syn and Blue soon realized that Naxy's intelligence was outdated and that Isen was no longer on Daluuj.

In reality, Isen was aboard the War Hammer, the flagship of the First Sith Imperial Strikeforce, and had joined Lord Azard and Moff Rulf Yage to oversee the poisoning of Da Soocha, where Mon Calamari refugees had been granted sanctuary by Azzim Anjiliac Atirue. Da Soocha was infected with the same toxins as Dac, while Da Soocha's moon, Napdu, was subjected to a massive orbital bombardment. Afterward, Isen celebrated the victory and referred to Yage as the "Conqueror of Da Soocha."

On Utapau, Isen, accompanied by Darth Azard, established a laboratory where he conducted experiments on native Utai and Pau'an subjects. The Givin planned to assassinate Gar Stazi and subsequently release a new plague that would adapt to any living species.

Skywalker's comrades, Jariah and Blue, foiled Isen's assassin, while Cade and Jedi Master Wolf Sazen confronted Isen and Darth Azard. Isen attempted to flee as Cade pursued him. On the ledge, Isen drew his lightsaber and engaged Cade in combat. During the duel, both sensed Darth Krayt, who had returned from the dead. Soon after, Isen leaped into the sinkhole to release the vial. Cade followed, using the Force to propel himself toward Isen, bisecting him half before catching the vial containing the virus intended to purge Utapau, slowing it down, and preventing it from shattering. As a result, Utapau was saved.

Vul Isen, born on Korriban and indoctrinated into the ways of the One Sith from an early age, was destined for a career as a scientist rather than a warrior. He possessed a natural curiosity, refusing to accept information without proof and frequently questioning the decisions and orders of his superiors. Isen believed that this inquisitive nature was crucial to his success as a scientist. However, it did not endear him to other, more warlike Sith, who were blindly loyal and unquestioningly obedient to Darth Krayt and considered Isen to be an inferior Sith.

Isen was trained in the art of genocide and was adept at pacifying or annihilating entire populations. He viewed these acts as a game and derived pleasure from his work. He believed that breaking the will of a species was more enjoyable than simply exterminating them, considering it a more subtle task. Despite this, the sadistic Givin worked extensively with viral organisms capable of wiping out entire planets and drastically altering their environments, and he enjoyed experimenting with these organisms on actual populations. He was greatly excited by Darth Azard's plan to eliminate the refugees and the Mon Calamari Rangers in one fell swoop and found the Leviathan's ability to absorb sentients' life energies fascinating, even as he watched his creation reduce masses of Mon Calamari to nothing but empty shells.

Isen was also quite talkative, in contrast to the reticent and taciturn Azard, with whom he spent considerable time on Dac. He frequently discussed his preferences, detailed his plans and how he formulated them, mocked other individuals, including his superiors, who had annoyed him or displayed perceived incompetence, and outlined the capabilities of his creation, the Sea Leviathan. He was impatient and found it difficult to simply wait for events to unfold. His mind required constant stimulation, and during the search for the Mon Calamari Rangers, he irritated Azard with his constant questioning as to whether they had arrived yet.

Despite his inquisitive and independent nature, Isen was deeply loyal to Darth Krayt, his Empire, and its ideals. While Azard distrusted the Givin because he was not blindly obedient to his superiors like many of the Sith warriors, Isen ultimately revealed his true allegiance to the Quarren Sith, rescuing him from the wreckage of the crippled Imperial shuttle. This surprised Azard, who had expected Isen to prioritize his own safety and abandon the injured Quarren. However, Isen explained that Krayt would have wanted members of the One Sith to protect each other and that they must follow their master's orders.

Isen's primary skills lay in the realm of science, and he engineered a number of experimental and deadly toxins during his career. He was also capable of using Sith alchemy to create a Leviathan adapted for use in the sea, although the idea originated with Darth Wyyrlok, an expert in Sith lore, rather than Isen himself.

Despite his membership in the One Sith, Vul Isen was not destined to be a warrior. He admitted that he lacked exceptional skill with a lightsaber, which was one of the reasons he did not attain the rank of Darth. He did not carry a lightsaber during his service to Krayt's Empire. However, he possessed rudimentary abilities with the weapon, using it to free Azard in the shuttle and defend himself against Cade Skywalker for a brief period.

Although his focus was on research and bioengineering, Isen was still capable of effectively wielding the Force. Alongside Darth Azard, he invoked the dark side on Dac to awaken the Sea Leviathan, projecting his mind into the abyss where it was located and imprinting his will upon it. As they did so, a surge of Sith lightning engulfed them. The Givin was also adept at telekinesis, using it to retrieve Azard's dropped lightsaber aboard the AT-AT on Dac and to shatter the vessel's window, creating a means of escape. Isen was a proficient swimmer and could swim great distances due to his Givin physiology, which allowed him to survive in a vacuum.

The character of Vul Isen was conceived by John Ostrander for the Fight Another Day story arc in his Star Wars: Legacy comic series. Isen made his debut in the first issue of the arc in January 2009 and subsequently appeared in the second issue in February. In both issues, he was illustrated by Omar Francia. In all of his subsequent appearances, he was drawn by Jan Duursema.