A mission to Prakith was undertaken in 137 ABY by the Sith Lord Darth Wyyrlok III, chief lieutenant of Darth Krayt's One Sith Order. The necessity of the mission was born out of a need by Wyyrlok's Master, Krayt, to rid himself of the Yuuzhan Vong implants that were threatening to end his life. After tirelessly researching ancient Sith secrets for answers, Wyyrlok consulted a Sith holocron in his possession, that of the long deceased Dark Lord Darth Andeddu, who was known to have preserved his essence for a time after his own death. Wyyrlok then traveled to the Deep Core to Andeddu's homeworld of Prakith, searching for information that would assist Krayt.
Wyyrlok managed to find Andeddu's Keep, where he encountered a previously unknown Sith cult called the Malevolence—one that worshiped Andeddu, and also refused to allow Wyyrlok further entry into their domain. Wyyrlok would not be denied, however, and he killed all the cultists save one named Gerlun, who revived Andeddu's deceased corpse at the cost of his own life. Andeddu then engaged Wyyrlok in a duel of Force abilities, a battle that Andeddu ultimately lost. With the ancient Sith Lord dead for a second time, Wyyrlok returned Andeddu's body to its sarcophagus and sealed it within.
Wyyrlok's mission was partially unsuccessful, as he was still unable to obtain any information in Andeddu's vast collection of Sith lore that would help him in the preservation of Krayt's life. He did, however, recognize what was truly killing the Dark Lord—his own doubts that he would not survive to see his dream of a stable galaxy under Sith rule fulfilled.
Darth Wyyrlok explores the interior of Andeddu's Keep.
Decades before the end of the Sith–Imperial War and the onset of the Second Imperial Civil War, A'Sharad Hett, who would become Darth Krayt, Dark Lord of the Sith, had been captured by the extra-galactic Yuuzhan Vong species and implanted with their Yorik-Kul slave seeds. Though able to combat the effects of the seeds through his growing strength in the dark side of the Force, Hett was slowly losing his battle with them. By 137 ABY, he had assumed the mantle of Dark Lord and restyled himself as the Dragon of the Sith, but the coral seeds still threatened to turn him into a mindless shell of a man.
For years Krayt was able to sustain himself through healing trances and extended periods of stasis, and he was looked after by the most trusted of his servants, the latest of them being Darth Wyyrlok the third. Despite being the most learned of Krayt's Order in Sith lore and ritual, Wyyrlok was unable to find a way to cure that which afflicted his Master. Thus, he consulted a holocron in his possession, one that belonged to an ancient Sith Lord named Darth Andeddu, who was known to have reanimated his flesh after his own death. The gatekeeper of Andeddu's holocron refused to reveal its secrets to save Krayt, whom it considered a pretender to the Sith legacy. Only after Wyyrlok alluded to actually reviving Andeddu's body did the gatekeeper reveal the location of Andeddu's Keep, on his homeworld of Prakith. Wyyrlok immediately set out in his personal fighter to the Deep Core, in search of Andeddu's domain and his coveted life-sustaining abilities.
Once arriving on Prakith with Andeddu's holocron, Wyyrlok entered the dilapidated fortress of Darth Andeddu, and was soon confronted by members of the Malevolence cult, guardians of Andeddu's tomb. Refusing to allow Wyyrlok to pass, they approached him with ignited lightsabers, intent on killing him. However, Wyyrlok displayed his proficiency with Sith sorcery, using illusions to trick the cultists into killing each other. All perished except for one, Gerlun, who swore fealty to Wyyrlok and led him to Andeddu's tomb. With Andeddu's holocron in hand, Wyyrlok was instructed by its gatekeeper to place the holocron on Andeddu's body to revive him, and thus learn all his secrets. Wyyrlok refused and was instead content with simply learning what he could from Andeddu's vast collection of books and scrolls. In an attempt to avenge himself on Wyyrlok for defeating his fellow cultists earlier, Gerlun used the Force to grab the holocron and placed it on Andeddu's body, and to both of their surprise, the holocron's power was burned out, as Gerlun's own life force was drained to restore Andeddu's life.
Darth Wyyrlok battles Darth Andeddu with Sith sorcery.
Although Andeddu had been revived, he refused to share his knowledge with Wyyrlok, stating that he believed that true Sith did not share power. He then attacked Wyyrlok with a barrage of Sith lightning, but Wyyrlok absorbed it in the palm of his hand. Andeddu challenged Wyyrlok to a duel of Force abilities, immediately Force-pushing him away while creating illusions of massive rocks, which he then hurled at Wyyrlok.
Wyyrlok was not so easily bested, and he quickly saw through Andeddu's tricks. He realized that Andeddu had a fear of death, and he took control of Andeddu's illusions of lava and flames to seemingly destroy all of Andeddu's books and scrolls. Mortified by the destruction of his precious artifacts, Andeddu believed Wyyrlok's illusion to be real even as Wyyrlok turned the lava and flames against his opponent. Andeddu perished a second time, consumed by his own fears of dying.
Wyyrlok placed Andeddu's soulless body back into its tomb and proceeded to study much of the lore in Andeddu's collection. However, nothing that Wyyrlok found in Andeddu's Keep spoke of any way to heal or preserve life through the dark side of the Force. What Wyyrlok did realize was that more than just physical affliction was killing Darth Krayt—his doubts of living long enough to ensure stability in the galaxy were having an equal effect on him as were the Vong slave seeds. Taking several books and scrolls, Wyyrlok left the keep and returned to his Master, even more determined to find another way to heal him.
Darth Wyyrlok discusses Karness Muur's healing abilities with Darth Krayt.
Eventually, Krayt did uncover a way to finally rid himself of the seeds but was unable to make full use of the power. Sometime after Wyyrlok's mission to Prakith, Krayt was lured into a trap by the Jedi and Imperial Knights of the Fel Empire, where he briefly subjected himself to the healing powers of the ancient Sith spirit of Karness Muur, who was using one of the Jedi as a host body. When the trap was sprung, Krayt was mortally wounded by one of the Imperials, shortly after figuring out how Muur was killing the slave seeds. When Wyyrlok found him to be alive, Krayt requested that Wyyrlok place him in a bacta tank so that his current wounds could be healed while he grew strong enough to complete the purging process that Muur had started. Instead, Wyyrlok enacted one of the core philosophies of the Sith and betrayed his Master by murdering him.
The mission to Prakith first appeared in the twenty-seventh issue of the Star Wars: Legacy comic series titled Into the Core, by writer John Ostrander. Ostrander uses this mission to expand somewhat on the backstory of Darth Andeddu by introducing both his homeworld and the Malevolence cult. Ostrander reveals here that it is not just the Yuuzhan Vong implants that threaten Darth Krayt's life, but that his doubts and fears play into his failing condition as well.