Mission to Tython In the year of 990 BBY , a Sith Lord known as Darth Bane undertook a mission to find the holocron of Belia Darzu on the planet Tython . Prior to the mission , Lord Bane had made several unsuccessful attempts at constructing a Sith holocron of his own . Due to efforts of his apprentice , Bane confirmed that the secrets to creating such a device were located inside the fortress of the deceased Dark Lord Belia Darzu . To uncover these secrets , Bane traveled to the fortress ' s location on the Deep Core world of Tython , hoping to find the information inside Lord Darzu ' s own holocron . After traveling to Tython and infiltrating Darzu ' s fortress , Bane eventually made his way into a large underground chamber . There , he located his target alongside the remnants of Darzu ' s technobeast army , the Metanecrons . These mutated organic - metal hybirds swarmed against the Sith Lord as he attempted to seize the holocron of their deceased creator . Nonetheless , Bane single - handedly slaughtered the creatures and went on to claim his ultimate objective . Within the holocron of Belia Darzu , Bane gained new insight into a ritual that would finally allow him to construct a holocron of his own . Prelude . In the aftermath of the New Sith Wars , a Sith Lord by the name of Darth Bane sought to create his own holocron , a device capable of harnessing the essence of its creator and storing their knowledge . After several unsuccessful attempts at constructing such a device , Lord Bane reached an impasse in his efforts , though he nonetheless refused to give up . At a later date , his apprentice , the Human female known as Darth Zannah , encountered an individual called Hetton , a dedicated researcher of Sith artifacts and lore . In their meeting , Hetton divulged information regarding Belia Darzu , a deceased Dark Lord of the Sith who stored her knowledge of creating holocrons inside a hidden fortress . In exchange for a datacard containing the fortress ' s location on the planet Tython , Zannah agreed to join forces with Hetton against Darth Bane . This was merely a ruse , however , resulting in Hetton ' s death during his later encounter with Bane . With the information collected by his apprentice , Bane embarked on a new mission to find the fortress of Belia Darzu , and with it , the secrets to creating a Sith holocron . Mission . In preparation for his mission , Darth Bane analyzed the datacard acquired by his apprentice , learning as much as he could about the Dark Lord Belia Darzu . Confident about the legitimacy of Hetton ' s research , the Sith Lord confirmed that his new target , the holocron of Belia Darzu , contained key information that would allow him to construct a holocron of his own . To reach the fortress where the device was being held , Bane used his personal startfighter , the " Mystic " , to traverse into the Deep Core , a region of the galaxy where the planet Tython was located . Traveling alone , he successfully navigated the hazardous hyperlane s of the Deep Core and arrived at Tython . Detecting no lifeforms within Lord Darzu ' s fortress , Bane converged on its location , only to have his vessel fired upon by a pair of automated tower - mounted ion cannons . Using his piloting skills , Bane evaded the barrage and destroyed the turrets , allowing the Sith Lord to land a short distance away from the fortress . As he approached the fortress ' s entrance , Bane used the power of the Force to blast open the front gate , providing him access to the building ' s interior . Within the fortress , Bane explored the facility room by room for any sign of his target . In this time , he briefly looked upon the remaining parts of Darzu ' s alchemical research , though eventually Bane refocused his attention towards locating the holocron of the deceased Dark Lord . During his excursion in the fortress , Bane felt the power of the dark side lingering throughout its halls , prompting him to seek out the source of this energy . This search led Bane into an underground section of the fortress , revealing a large chamber that served as an inner sanctum . Inside this chamber , Bane finally discovered a pedestal in the middle of the room holding his ultimate prize — Lord Darzu ' s holocron . Surrounding the device , however , were the remnants of the Metanecrons , an army of mutated cyborgs known as technobeast s . When Bane drew closer to the pedestal , the technobeasts initially ignored him completely . Immediately as he attempted to seize the holocron , however , the creatures became enraged and attacked the Sith Lord in a swarm . With both the Force and his lightsaber , Bane defended himself and destroyed several of the technobeasts , using his orbalisk armor for protection against their melee attacks . In his battle against the creatures , Bane was abruptly pummelled by one of the larger mutated rancor variants . The attack hurled the Sith Lord face - first into a humanoid technobeast that infected him with the nanogene spore , a virus that transformed living beings into the metal - organic hybrids themselves . Once again , however , the orbalisk s on Bane ' s armor saved his life , purging the virus from his body and preventing it from lobotomizing his brain . As the effects of the nanogene spore subsided , the Sith Lord launched a counterattack against the rancor , ultimately destroying it and continuing his fight against the remaining Sithspawn mutants . Despite the relentless aggression of the technobeasts , Bane single - handedly destroyed all of the creatures in the chamber . After a massacre that lasted for over an hour , Bane took but several minutes to recover — both physically and mentally — before finally claiming the holocron of Belia Darzu . Aftermath . With the holocron in his possession , Darth Bane began to scour its contents , interacting with the device ' s gatekeeper in the form of an avatar depicting Belia Darzu . While doing so , Bane came across a set of instructions detailing the entire process of building a holocron . Though he was already familiar with most of this information , one particular element of these instructions had eluded him up to this point : the trapping of the creator ' s essence into the capstone of the holocron . After Bane questioned the gatekeeper on this process , the holocron depicted a Sith ritual known as the Rite of Commencement . Despite the complexity of the ritual , of which Bane mused would likely take him months to memorize , the Sith Lord was nonetheless satisfied with the new insights he had gained . Behind the scenes . The mission to Tython first appeared in " " , the second adaption of the " Darth Bane " trilogy authored by Drew Karpyshyn .