Kao Cen Darach, born in 3681 BBY, was a distinguished male Zabrak who achieved the rank of Jedi Master within the Jedi Order during the years just prior to the Great Galactic War. Darach, a celebrated Jedi Knight and later Battlemaster, mentored a young Jedi Padawan, Satele Shan. Shan accompanied him on a space station that was in orbit around Korriban, the homeworld of the Sith. Also present were Corporal Jace Malcom and Nico Okarr, a smuggler who was being held imprisoned. Unexpectedly, the station came under attack from the Sith Empire, a group thought to have been gone for centuries, who were trying to reclaim their planet. To warn the Galactic Republic, Darach and Shan freed Okarr. As they hurried to the hangar, they battled the invading Imperial soldiers.
Upon reaching their destination, two Sith, Vindican and Malgus, confronted Darach and Shan, initiating a lightsaber combat. During the duel, the Jedi Master had to shield his apprentice from Malgus's blade. He then told her to escape on Okarr's quickly departing ship. Choosing to stay behind, Darach continued to fight the Sith, now wielding Shan's double-bladed lightsaber. Darach was able to defeat Vindican, leaving him injured. However, he was subsequently killed by an enraged Malgus. Shan managed to escape and alert the Republic about the Sith Empire's return due to her Master's self-sacrifice.
Kao Cen Darach, a Jedi Master of the Zabrak male variety, dedicated his service to both the Jedi Order and the Galactic Republic in the years leading up to the Great Galactic War in 3681 BBY. Many years prior to the war, Darach crossed paths with a young Miraluka named Shol Bestros who had consistently declined joining the Order throughout his youth. Identifying the youth's inherent talents, Darach successfully persuaded Bestros to embrace the path of a Jedi. Bestros eventually attained the rank of Jedi Master around the time the Great Galactic War began, later serving as a member of the Jedi Council.
Darach also occupied the role of Battlemaster within the Jedi Order, a designation given to the foremost instructor in lightsaber combat among the Jedi. He served on the Republic's capital, Coruscant, during the years preceding the war. However, his strong ideals and unwavering stance against any manifestation of the dark side of the Force caused friction with the Jedi Order's political position on the world. During his tenure as Battlemaster, Darach authored a text titled Combat Techniques of a Jedi Battlemaster.
Eventually, the Zabrak was assigned to the security space station positioned above the planet of Korriban, the original homeworld of the seemingly extinct Sith Empire. During his time on the station, the young Jedi Padawan Satele Shan came to study under him, learning about the nature of the dark side and the proper use of a double-bladed lightsaber. Throughout their shared time, Darach not only trained her in lightsaber combat but also guided her through her trials, enabling her to become a fully recognized Jedi Knight.
In 3681 BBY, the pair journeyed to Korriban's surface to intercept Nico Okarr, a smuggler who was in the process of attempting to acquire stolen Sith artifacts from a notorious grave robber known as Farel Wickes. Working alongside Republic Army Corporal Jace Malcom, the two Jedi apprehended Okarr, confiscated his freighter Redshifter, and placed him into custody. Despite Okarr's insistence on his innocence during the escort to the space station for incarceration, Master Darach dismissed his explanations. Darach then questioned his Padawan when he noticed Shan appeared disturbed by something she sensed approaching. The reason for her discomfort was revealed when the resurgent Sith Empire, which had been absent from the galactic scene for centuries, attacked the defending Republic forces, aiming to reclaim their ancestral homeworld.
Darach's main focus was to warn the Republic about the Sith's return to the planet. Given that none of the station's shuttles could outpace the Sith fighters, Okarr offered his own vessel, claiming it to be the fastest in the sector. Darach, Shan, Okarr, Malcom, and another Republic trooper fought their way to the station's hangar, facing significant resistance from Sith boarding parties. The group eventually reached the landing bay, although the troopers were killed during the process. After defeating several Sith troopers in the hangar, Darach and Shan were confronted by the Sith Lord Vindican and his apprentice, Malgus, who had arrived to prevent the Jedi's escape. While the Jedi and Sith dueled, Okarr and Corporal Malcom prepared the impounded Redshifter for departure. Darach held his own in combat against the Sith, but Shan did not fare as well, and narrowly avoided being slain by Malgus thanks to Darach's timely lightsaber throw.
Following the initial clash, Darach used the Force to push Vindican away as Okarr's ship began its ascent, with Malcolm urging the Jedi to join them. Instructing Shan to board the starship and escape, Darach remained behind to confront the two Sith, effectively sacrificing himself. As her master charged back into the fight, Shan threw her double-bladed lightsaber to him, which Darach used simultaneously with his own lightsaber to prolong the battle, buying her more time to escape. Despite being outnumbered, Darach proved to be a formidable match for Vindican and Malgus, even managing to mortally wound Vindican. Malgus took his Master's lightsaber with the Force and moved towards Darach, who used the force to throw large pieces of wreckage towards the Sith. Malgus cut through the pieces with his lightsaber, jumping through the last one and launching a brutal, rage-filled assault on Darach, which eventually succeeded in slaying the Jedi Master. Shan felt Darach's death in the Force but continued on to warn the Republic of the Sith's return.
Ultimately, Darach's sacrifice allowed the Republic to become aware of the Sith's resurgence, preventing them from being completely unprepared for future Sith attacks. Shan, Darach's Padawan, also continued to fight against Sith forces in various conflicts and eventually rose to become the Grand Master of the Jedi Order, an achievement made possible only by Darach's willingness to save her life at the expense of his own. Later in her life, Shan would note in her annotations of the Jedi historian Gnost-Dural's journal that she felt she owed a debt to Kao Cen Darach—a debt that she was still making an effort to repay over thirty years later. Darach was eventually succeeded as Battlemaster by Jedi Master Jun Seros, who held the position during the Cold War. Seros himself would ultimately meet his end at the hands of the Grand Champion of the Great Hunt, being succeeded himself by the Hero of Tython.
Kao Cen Darach, a male Zabrak without hair, possessed light skin, green eyes, and the typical cranial horns characteristic of his species. The Zabrak Jedi Master adhered strictly to his own firm belief system, which emphasized the need to confront and defeat the dark side of the Force, regardless of its manifestation. His distinct, uncompromising approach to matters concerning the Force made him an unpopular figure among the higher-ranking members of the Jedi Order on Coruscant—a fact that did little to deter the principled Jedi. Darach's assignment over Korriban was thought to be a result of this uncooperative political attitude, but Satele Shan would later suggest that Darach's opposition to the dark side motivated him to seek the assignment himself. Regardless of the reason, Darach's reputation as a determined fighter against the dark side attracted the young Shan, who hoped to learn the Zabrak's philosophy through an apprenticeship.
During the battle with the Sith, Darach showed remarkable bravery and readily engaged in combat despite being outnumbered. Darach was a very stoic and calm figure, and did not break his composure, even when in heated combat. By this time, he had forged a close relationship with Shan, and was immediately able to tell when something was troubling her. He was concerned for Shan's well-being during the conflict and even intervened on her behalf during combat aboard the Korriban space station.
Holding the esteemed titles of Jedi Master and Battlemaster within the Order, Kao Cen Darach stood out as an exceptionally skilled warrior whose mastery of lightsaber combat was unmatched among his peers. In battle, Darach wielded a green single-hilt lightsaber, demonstrating his capability to simultaneously handle both a Sith Lord and his apprentice. Darach also showcased a combat style that involved the simultaneous use of a double-bladed lightsaber and a single-hilt lightsaber, thus employing an unorthodox form of Jar'Kai. In fact, he was the one who taught Satele Shan how to use a saberstaff. His combat abilities enabled him to eventually defeat Vindican, but he was ultimately overwhelmed by Malgus's rage and brute strength; however, Malgus had been one of the Sith Empire's most seasoned fighters long before the attack on Korriban, so Darach's defeat could only be circumstantial.
Regarding his Force abilities, Darach possessed significant telekinetic power, enabling him to hurl large objects, such as pieces of starships, and repel opponents during combat. His level of control allowed him to throw his lightsaber with precision and effectiveness. Satele Shan believed that Darach may have been a capable seer, and that a vision of the Sith Empire's return was what drew him to Korriban.
Master Darach wore a complete set of armor, consisting in a suit with metal plates attached on his torso, arms, and legs underneath his standard Jedi robes. Such armor design would later became common for Jedi fighting in the Great Galactic War. As it was tradition for the Jedi, the Battlemaster featured a green-bladed lightsaber at his side that featured a metallic handle and a single blade.
Kao Cen Darach made his initial canon appearance in the Return cinematic trailer, which was launched on June 6, 2011 for LucasArts's Star Wars: The Old Republic video game, which was developed by BioWare. Although Darach had spoken lines, he was not named in the trailer and remained unidentified until a wallpaper displaying his name was subsequently released on The Old Republic's official website. The Journal of Master Gnost-Dural, included in collector's editions of The Old Republic, narrated the events surrounding the fall of Korriban and featured notes and images of Kao Cen Darach. The Journal of Master Gnost-Dural and The Old Republic were released together on December 20, 2011. Within the video game, players can acquire and equip an armor set known as Jedi Stormguard, which bears a striking resemblance in design and color scheme to the armor worn by Kao Cen Darach in the Return cinematic.
The 2012 reference guide Star Wars: The Old Republic Encyclopedia identified Darach as a Jedi Battlemaster, and also gave additional backstory about both Shol Bestros and Darach. In the Encyclopedia, Darach was listed alongside Revan and Ven Zallow under "Notable Jedi Knights", and he was also the sole entry in the "Notable Zabrak" field in the infobox for the Zabrak species. In summer 2013, a LEGO model of the Defender-class light corvette—titled the "Jedi Defender-class Cruiser"—was released that includes a minifigure of Kao Cen Darach.