Xor, a male Twi'lek, functioned as a Mandalorian slaver. He participated in the Battle of Cathar before the Mandalorian Wars, where he took part in the speciecide of the Cathar people. Twenty years after the Mandalorian Neo-Crusaders invaded the planet Taris, Xor murdered a Cathar male. He then located the Cathar's daughter, Juhani, on Taris's auction blocks, but Jedi forces liberated Taris before the Twi'lek could buy her. During the Jedi Civil War in 3956 BBY, Xor encountered Juhani, by this point a Jedi, assisting the Padawan Revan in his search for the Star Forge, a Rakatan space station powering the Sith Empire's war against the Galactic Republic. Shortly after, Xor and two accomplices attacked Juhani and Revan near Revan's starship, the Ebon Hawk. The Jedi defeated Xor and his allies. The injured Twi'lek attempted, unsuccessfully, to provoke Juhani into killing him before he died from his injuries.
A male Twi'lek, Xor served as a Mandalorian slaver in the era following the Great Sith War. In 3973 BBY, when Mandalorians under Cassus Fett's command attacked Cathar, the planet he orchestrated the battle on, Xor participated by killing numerous Cathar people. Driven by his hatred for the Cathar, the Twi'lek enjoyed the carnage. Despite the Mandalorians nearly wiping out the Cathar, Xor was injured during the battle, preventing further combat involvement.
Twenty years later, during the Mandalorian Wars, Xor was involved in the Mandalorian Neo-Crusaders' invasion of Taris. Sometime after that, Xor encountered and murdered a Cathar male in the Lower City, but his wife and daughter, Juhani, escaped him. Two years after, Xor saw Juhani and tried to purchase her from the auction blocks, but Jedi forces under Revan, a Jedi Knight, liberated Taris, freeing Juhani from slavery.
During the Jedi Civil War in 3956 BBY between the Republic and Darth Malak's Sith Empire, Xor encountered Juhani, now a Jedi, assisting Revan, a Padawan who had formerly been a Dark Lord of the Sith and had undergone retraining, in his search for the Star Forge. The Star Forge was a Rakatan space station fueling the Sith war against the Republic. Xor attempted to convince Revan to sell Juhani to him, insulting the Cathar. After Revan refused and Juhani threatened to kill Xor for his actions against her people, the Twi'lek vowed to confront them again and capture Juhani.
Near Revan's starship, the Ebon Hawk, Xor and two cronies ambushed Revan and Juhani. However, the Jedi mortally wounded the Twi'lek, and his thugs were defeated. As Xor died, he tried to provoke Juhani into striking him down. Revan recited the first precept of the Jedi Code, which denied emotions and encouraged peace, to prevent her from succumbing to her anger. Xor then died, angered that his death was ignorable.
Xor, who had purple skin and eyes, used a blaster rifle in combat. He hated the Cathar and wanted to either eradicate or enslave them. He was among the Mandalorians who attacked Cathar for the pleasure of destroying it. He viewed Cathar slaves as pets for their owners' amusement. Despite being injured on Cathar, he continued fighting with the Mandalorians. Xor killed Juhani's father on Taris and was prepared to buy Juhani at auction during the Mandalorian occupation. Later, during the Jedi Civil War, he taunted Juhani and asked Revan if he wanted to sell her to him. After being defeated by Revan and Juhani, Xor tried to pressure Juhani into murdering him. He also resented the Jedi for hindering his acquisition of slaves during the Mandalorian Wars.
BioWare created Xor as a minor villain for the 2003 Star Wars: Knights of the Old Republic video game. Neil Kaplan voiced him. In the Xbox version, Xor is a Human, while in the PC version, he is a Twi'lek. Some in-game comments suggest he was Human. However, in 2008, the Knights of the Old Republic Campaign Guide officially canonized Xor as a Twi'lek. In the game, he appears only after the player learns all about Juhani's past. If the player visited the spaceports on Tatooine, Kashyyyk, Manaan, or Korriban with Juhani, Xor would confront them. Alternatively, the player can convince Juhani to kill Xor. He never appears if Juhani was killed on Dantooine.
Xor is the only purple, male Twi'lek, and one of only two purple Twi'leks in Knight of the Old Republic, with Yuthura Ban being the other.