"What I espouse is not knowledge, but wisdom; the difference being that while you may have lived events I can only experience through literature, I can, unlike you, explain why they matter."
— Nubis Serin to Disciple Malevolence
Darth Ulterius, born Nubis Serin, was a Force-sensitive Human male who rose to prominence as a Sith Lord in the Dark Lords of the Sith. Awakened in his teenage years by Darth Coelus, an ancient Sith whose spirit was locked inside a holocron, Nubis later came to be trained by Darth Infestus.
Early Life (200–221 ABY)
"Listen to me! We're simple farmers; we can't afford to waste our time and energy rooting around in old ruins. Grow up!"
— Berand Serin
Nubis was born in 200 ABY on Dantooine, the only child of Berand Serin and his wife, L'lena. He was raised at the Serin family homestead in the Fields of Banir near Khoola Settlement.
Early in his childhood, Nubis had taken to exploring the ruins of a Jedi temple maintained by locals for centuries. Though the ruins had been picked clean of valuables long before the area was resettled, Nubis managed to collect a handful of trinkets he found buried under a lopsided column. One of the artifacts was a stone tablet inscribed in the ancient Sith language and which featured an arrangement of crude geometric patterns.
In 221 ABY, while delivering crops for his father to the Khoola spaceport, Nubis encountered a man named Kelin Rex, a fellow at the Coruscant Museum of Galactic Cultures. Nubis, eager to learn more about his growing-collection of treasures, brought Rex to the shed where he kept his collection hidden from his parents. Rex showed great interest in the stone tablet Nubis found years earlier, and explained he could translate the text, but it would require a night of study and access to the HoloNet. Knowing that the nearest HoloNet terminal was in the capital, Garang, Nubis reluctantly agreed to allow Rex to take the tablet overnight on condition that he would return it by midday the next day. The scholar never returned. Several days later, Nubis tracked Rex to Garang and discovered the man had rented a speeder, intending to head north into the mountains. Following his trail, Nubis arrived only to stumble upon the ruins of a Sith temple carved into the cliffs. He eventually found his stone tablet in the hands of a lifeless Rex at the foot of an old old blba tree which had its roots unearthed to expose a stone reliquary.
It was inside the reliquary that Nubis discovered the holocron of Darth Coelus, whose spirit appeared to the young man. The summoned Sith Lord immediately attempted to possess Nubis, a process which was interrupted when the blba tree suddenly collapsed. Rex and the tablet were buried along with the reliquary and holocron.
Fall to the Dark Side (221–227 ABY)
"Your son is gifted, L'lena. Don't you see? The strange visions, speaking in tongues, and the artifacts? He is so much more than you allow him to be. I will take him from here--to a place he can realize his potential."
— Lord Haesh
The Holocron of Darth Coelus
Nubis remembered little of what transpired in the mountains or how he managed to find his way home. Wracked by hallucinations and painfully dehydrated, he stumbled into the family homestead three days after he set out in search of Kelin Rex. He said nothing of his nightmares, but what he couldn't hide were the physical changes; to his parent's horror, Nubis' eyes had completely drained of color and his once dark hair had turned a pristine white.
In the days and months that followed, the visions and nightmares continued, disrupting his sleep almost nightly. Worried their son was suffering from an illness they could not treat, and looking for answers, his parents sent him to doctors in Garang. It was determined that Nubis was suffering from stress and exertion--which convinced his parents to ease up on his duties around the homestead. Nubis took advantage of the extra time by sneaking out and venturing into Khoola to buy trinkets from spacers or to the ruins to unearth more secrets.
By 227 ABY, his collection rivaled that of the Dantooine History Museum; totaling over 4,000 individual items, Nubis was forced to hide his artifacts in different locations around the homestead, though most ended up buried in crates beneath the crops. Unbeknownst to Nubis, his cache generated a unique and concentrated presence in the Force which piqued the interest of a passing Sith Lord, Haesh.
It didn't take long for Haesh to track down the Serin Homestead, where she observed--in secret--the lives of Nubis' family for seven days before approaching Nubis in the middle of the night as he returned from one of his clandestine outings to the spaceport. She revealed to him that she had been watching his activities, and despite the obvious illegality of his actions, she was planning to offer Nubis a scholarship to attend a prestigious academy in the Core. This was only a half-truth, of course, as while Haesh did hail from a prestigious academy, she was secretly referring to the Sith Academy on Byss. With assurances that things would be taken care of, Nubis agreed to speak with his parents and arrange a dinner meeting between them and Haesh.
The meeting took place the following night. Nubis' parents were dubious about the idea of their son attending an academy, let alone one being peddled by such a mysterious woman who seemed reluctant to offer any concrete information. L'lena, in particular, worried about how such a move would affect Nubis' health. Ultimately, however, Haesh was able to convince both Berand and L'lena to let Nubis make the decision for himself. With Haesh leading the way, Nubis boarded a shuttle to Byss the next morning.
Acolyte of the Dark Lords (227–230 ABY)
"He is an idiot. Value your own life, think for yourself, independence--those are strong qualities. You are weak-minded."
— Disciple Drae'gath at Nubis' Evaluation
The three-day trip to Byss afforded Nubis an opportunity to learn more about Haesh and uncover the truth of what was happening to him. She instructed him about the Sith, the Empire, and the academy where he would be trained in the Dark Side. She also offered a cursory introduction to the Force and basic training in telekinesis--everything he would need to pass an evaluation to enter the Sith Academy and begin his path toward the Dark Side.