Beszael (Pronounced Bez-ay-el) is a Sith Lord in residence on the planet Korriban.
Beszael was born a human by the name of Khar Toba, the only son of Jedra and Myra Toba. They lived on the planet Dantooine as farmers and the young Beszael was raised as a farmer himself. Jedra and Myra had always known that their son was Force sensitive, but they had lied to him about his seemingly supernatural abilities over the fear that the Jedi might discover him and come to take him away to train him as one of their own.
At the age of seven, Beszael's parents were killed by a Mandalorian Raiding party. Often the farming community had managed to fend off these raids, but on this occasion fatalities had been taken and Beszael's parents had been among them. This tragedy represented his first step toward the Dark Side. Irresponsibly shielded from the truth of what he was, he had no notion that the Dark Side loomed over him and, enraged at the murder of his Parents, Beszael sought the Mandalorians and killed every one of them, his suppressed force powers flourishing for the first time and taking on a terrifying lethality.
Two days later, the Jedi discovered him at his parents' home. Filled with Anger and Hate the Jedi had no recourse but to attempt to explain the Force and why he must control his feelings, for Anger and Hate led to the Dark Side of the Force. The Jedi said that they would return for him the following day, after he had had time to contemplate their words and reach a calm state. But as night fell upon Dantooine, Beszael Fled, stowing away on a private yatch, his destination became the planet Coruscant.
The Path to the Dark Side
Khar had realised that the Jedi could not help him. He wanted revenge, not forgiveness. His parents had been humble folk and had not deserved their lives being cut short for the personal gains of Mandalorians. They deserved to be avenged. If the Jedi could not help him, then he knew who could.
Travellers had, when visiting Dantooine, spoken of a Great War occurring between the Jedi and a people known as the Sith. As an inquisitive young man, Khar had learned that the Sith represented the antithesis to the Jedi. Where the Jedi represented peace and light, the Sith represented Conquest, War and Darkness. The were, he learned, a people who had embraced their passion and turned the power of the Dark Side against others. This power, this 'Dark Side', now sounded appealing to Khar. He would have he revenge at any cost.
He found the Sith. Instinct, or something more, had brought him to Korriban a the Sith horde marched upon Coruscant, intent on raining destruction upon the Galactic Republic. He watched with awe as the Sith cast their dark powers upon the army of the Republic, hungered to possess that power also. Ambitions of a revenge exacted upon Mandolorians filled him. Death dealt by the powers of the Dark Side, greed filled him.
The Sith fell. Treachery from within had given the Republic the advantage they needed to beat the Sith back to Korriban. A deathly silence fell upon Coruscant after. Khar scrabbled through the ruination of fallen warriors, picking up redundant lightsabers to study.
It was then that he was approached by a dark figure. A Sith Lord who had survived the carnage, but had been left behind in the hasty retreat of forces. He sensed the potential in Khar and identified himself as [redacted]. Khar was taken under the wind of this shadowy creature and became an apprentice of the Sith. It would change his life forever.
Khar was reborn. He had taken a new name for himself: Darth Scaarus. Years passed and Scaarus' powers with the Dark Side as he grew into his early twenties. He showed skill in the areas of Sorcery, Alchemy and Carnomancy (Mastery of the Flesh). But his adeptness in this fields also made him cocky and eager.
After learning of the power to change one's physical appearance, Scaarus was eager to try it out. His Master had cautioned him on the dangers. The Mask was a quick process, but was agonizingly painful and came with a multitude of risks such as permanent deformity or even death.
This counsel, however, was taken too lightly by Scaarus. He did not have the mastery or the required tools to perform the procedure correctly, but was determined to master it anyway. He was determined to exceed his Master and so attempted it.
The result was a disaster. He became a runt. His body unable to decide which DNA was now dominant, his Human DNA, or the Barabel DNA that now wound through his being. He had picked the race at random, something suitably impressive, but not too extreme-a-change like a Hutt or a Houk.
His Master found him the following day as a nebulous husk that ever fluctuated all over, parts of his body switching from Human to Barabel to Human once more. His Master had more experience in the art of Alchemy and Carnomancy and was able to stabilise him, but for many years Scaarus had such an irregular appearance that he entombed himself within armor that completely covered him and wore a mask to hide his deformed face.
It took him years to recover. Learning the secrets of Carnomancy, he was able to craft his body into something much more stable. He could appear human, or any species he desired, but the hazards of the Magic he had attempted to perform had sentenced him to being unable to rid himself of the Barabel DNA ever again.
Records of this aspect of the life of Darth Beszael were intentionally deleted. Whatever means Beszael used to extend his life can only be speculated at. Some argue that he mastered the process first set in motion by Sith King Drathka Graush, other that the process was discovered from Darth Andeddu. Nobody really knows, and Beszael himself has never spoken of it.