Mystra functioned as an alien assassin and served as an enforcer for Raskar, a one-time pirate who was the sovereign of the planet called Antipose. Raskar orchestrated lucrative gladiatorial contests, offering a unique power gem as the grand prize; Mystra's role was to assist him in maintaining order on the planet, which involved killing people her employer deemed expendable.
In the year 0 ABY, the smugglers Han Solo and Chewbacca made their way to Antipose in their quest for a power gem. Mystra intervened in a dispute they encountered with a trio of challengers vying for the artifact. The enforcer escorted the pair to Raskar, who showcased the power gem to Solo and attempted to entice the smuggler into competing for it in the arena. Suspecting Solo might try to acquire the gem through unconventional means, Mystra attempted to use her proficiency with a wrist blaster to dissuade him.
Regardless, Solo eventually had Chewbacca initiate a spontaneous scuffle, observed by Mystra from a distance, with the top gladiator to create a diversion. This allowed Solo to infiltrate Raskar's villa and conduct a thorough scan of the power gem. Discovering that the artifact's capabilities had lessened over time—a detail Raskar had kept from all the competitors—Solo ultimately persuaded the former pirate to permit him and Chewbacca to depart with the gem. Raskar and Mystra both bid the smugglers farewell as they left the planet.
Mystra, a gunslinger and assassin, acted as a bodyguard and enforcer for Raskar, who governed the Centrality planet known as Antipose. Raskar, once a pirate, had established himself on Antipose, bringing with him a precious power gem—one of several uncommon artifacts made of a meteoritic mineral capable of disabling the deflector shields of starships. He then set up a series of gladiatorial contests, offering the power gem as the ultimate reward.
As time passed, many sought to participate in the gladiatorial bouts. Raskar amassed wealth through arena admissions—from spectators and participants alike—as well as a percentage of all gambling proceeds. Mystra aided the former pirate in maintaining control of Antipose by eliminating any individuals he deemed problematic. However, Raskar never revealed to Mystra that, in addition to a force field, the power gem, housed in a chamber at his villa in the planet's only city, was also safeguarded by hidden, destructive energy beams.
In 0 ABY, Princess Leia Organa tasked the smuggler Han Solo with locating and securing a power gem to assist the Rebel Alliance in their fight against the new Star Dreadnought, the Executor, belonging to the Sith Lord Darth Vader. Solo and his copilot, Chewbacca, journeyed in their light freighter, the Millennium Falcon, to the Tharin sector shadowport Junkfort Station to commence their search. There, an alien—secretly an agent working for Raskar and Mystra—directed them to Antipose, claiming to have seen a power gem there. After the smugglers left Junkfort Station, the agent informed Raskar and Mystra of their impending arrival.
After landing their ship at a landing zone outside Antipose's city, Solo and Chewbacca were quickly confronted by a trio of individuals who, also interested in acquiring the power gem, were attempting to intimidate potential rivals into leaving the planet. Before any shots could be exchanged, Mystra arrived on a floater, interrupting the confrontation and ordering the trio harassing Solo and Chewbacca to depart from Antipose. Addressing Solo by name and identifying him as a Corellian, Mystra then instructed the two smugglers to board the floater. She then transported them to the city, briefly showing them the Antipose Arena—informing Solo that people were willing to pay to fight for the power gem—before taking them to Raskar's villa.
Solo and Chewbacca met Raskar there, and Mystra was present when her employer, seeking to motivate Solo to compete in the gladiatorial contest in the arena, arranged a private demonstration of the power gem's capabilities. Raskar instructed Mystra to fire at the artifact—startling Solo, who was unaware of the force field protecting it—and then demonstrated the artifact's effect on the force field. As the crime lord Jabba had placed a significant bounty on Solo that Raskar wished to claim, he offered the smuggler free participation in the gladiatorial fights for the power gem. Solo agreed, provided his powerful Wookiee companion could fight in his place, with Raskar warning that he would use Mystra to prevent Solo from fleeing should Chewbacca lose in the arena.
Suspecting Solo would attempt to manipulate the gladiatorial contest system, Mystra confronted the smuggler and his partner after they left Raskar's villa. The enforcer displayed her weapon skills and tried to intimidate Solo into not cheating. Boarding her floater but remaining in contact with Raskar via comlink, Mystra observed Solo and Chewbacca from afar as Solo obtained directions to the training grounds of a massive alien gladiator who was the leading contender for the power gem. The smuggler had devised a plan to acquire the power gem without fighting in the arena. Solo convinced his companion to start a brawl with the gladiator, violating the planetary law against fighting outside the arena.
Mystra informed Raskar of the situation, and the former pirate instructed her to immediately stop the fight. The enforcer attempted to do so but determined that it was too late, given the growing crowd of spectators, believing they would riot if authorities intervened. Intent on punishing Solo for cheating him out of his profits from the fight, Raskar ordered Mystra to find the smuggler and then traveled from his villa aboard his own floater to assist her.
However, Solo used the distraction provided by the crowd to slip away unnoticed and sneak back into Raskar's villa. Mystra's employer was informed that the smuggler was slicing his way into the power gem's chamber, and he and Mystra hurried back to the villa. Raskar was confident that the power gem's defenses would deter Solo's attempts, and when the villa's alarm system indicated that the chamber's energy beams had fired, he assumed the smuggler had died and slowed down his floater, surprising Mystra. The enforcer speculated that Solo's death would make it easier for Raskar to collect the bounty on him.
Upon arriving at Raskar's villa, they discovered that Solo had tricked the former pirate's training droid into the path of the destructive beams. Solo had also used a portable scanner to determine that the power gem's ability to affect shields was diminishing and that it was only good for one more use against a starship. Initially, Raskar ordered Mystra to kill Solo to prevent the information from becoming public, and the enforcer expressed confidence that the smuggler could not escape her.
However, Solo convinced Raskar to declare Chewbacca the winner of the competition since the Rebel Alliance only needed to use the power gem once and had no interest in revealing Raskar's deception. As the plan depended on Chewbacca winning the fight against the gladiator, Mystra grew anxious as she observed via monitors that the Wookiee appeared exhausted. As she and Solo traveled to the fight, the smuggler explained to Mystra that becoming tired only enraged Chewbacca. When he informed his companion that their plan had worked and that he no longer needed to prolong the fight, the Wookiee quickly defeated his opponent.
Mystra and Raskar later saw Solo and Chewbacca off as they left Antipose with the power gem. The enforcer expressed their gratitude to the smugglers for allowing them to save their reputation, and her employer remarked to Mystra his admiration for Solo as a scoundrel. Raskar later faced financial difficulties and was forced to return to interstellar piracy.
Mystra was a mysterious and exotic green-skinned female alien. She considered gladiatorial combat an "interesting" and "practical" way to handle the competition for Raskar's power gem. Mystra had little respect for the arena's contestants, viewing them as overconfident "scoundrels" and believing the galaxy was full of such individuals. She also considered Han Solo "shifty" and a "schemer," but she admitted to Raskar that the smuggler had a certain charm.
When warning Solo and Chewbacca against cheating, Mystra boasted about her accuracy with her wrist blaster and her speed, leading Solo to see her as a real threat. However, Mystra soon realized that Solo would ignore her warning and pursue his own plan to acquire the gem. Mystra also had a vengeful side, suggesting to Raskar that Solo should "pay" for trying to subvert the gladiatorial arena system.
A professional killer, Mystra was observant enough to notice that, during a confrontation, Han Solo had positioned himself to take advantage of the sun and set up a crossfire with Chewbacca. Mystra speculated that Solo's opponents would not have survived the encounter.
Mystra wore a dark red jumpsuit with yellow accents, including a belt and gauntlets, and yellow boots. She also wore a yellow-and-dark-red cybervision helmet that obscured her eyes and ensured perfect aim. A pair of lethal wrist blasters, capable of delivering a sting-level blast and causing a large explosion, were mounted on Mystra's gauntlets and connected to her helmet's red visor by cables. Mystra also used a yellow-and-green floater, similar to Raskar's, with controls at the front and room for at least two passengers.
Mystra is a secondary antagonist in "The Power Gem," a comic story written by Archie Goodwin, drawn by Al Williamson, and published between July 26 and October 3, 1982 as part of the daily black-and-white Star Wars comic strip distributed by the Los Angeles Times Syndicate to major American and Canadian newspapers from 1979 to 1984. A reprint of "The Power Gem," colored by Steve Buccellato and included in the August 1993 eleventh issue of the Dark Horse Comics' Classic Star Wars comic-book series, established Mystra as a humanoid alien a decade later.