Cypher Bos, a Nalrithian of ill repute, was a bounty hunter of considerable fame during the Galactic Civil War. While primarily in the employ of the Galactic Empire, he also took contracts from Jabba Desilijic Tiure, thereby solidifying his image as a ruthless and skilled pursuer.
In the year 3 ABY, Cypher sought out his egg-sibling, Phoedris Bos, with the sinister intention of murdering him and assuming his identity to infiltrate the Alliance to Restore the Republic. Having learned of Phoedris's involvement in an upcoming mission alongside Han Solo, he envisioned a single act that would cripple the Alliance and secure Solo's valuable bounty. The confrontation between Cypher and Phoedris took place on Ord Mantell; exploiting their shared mental connection—a consequence of their shared hatching—to glean crucial Rebel codes, Cypher ultimately killed his own brother.
Solo's arrival occurred several weeks later, and Cypher was instructed to guide him and his companion to an Imperial computer terminal for system access. Upon recognizing Solo's companion as none other than Leia Organa, Cypher abandoned his disguise and took them both as hostages. However, Solo managed to disarm him, and following a brief exchange of blaster fire, the Nalrithian bounty hunter met his end.
Cypher Bos, an insectoid Nalrithian, was one of four siblings hatched simultaneously. Driven by a crude desire for wealth, he possessed a mental link with his three siblings, allowing them to share memories and sense each other's presence within a range of approximately twelve meters. Moreover, the four Nalrithians experienced shared pain when in close proximity; however, this did not deter them from harming one another, and at some point in his life, Cypher tracked down and eliminated two of his eggmates. Phoedris Bos, the third sibling, was significantly stronger than the two Cypher had previously killed, making Cypher hesitant to engage him in direct combat.
Cypher embarked on a career as a bounty hunter, cultivating a reputation for both competence and unscrupulousness. He operated within the same echelon as renowned figures such as Boba Fett, Skorr, and Beilert Valance, commanding fear and respect from most individuals he encountered. Nalrithians were generally feared throughout the galaxy, Cypher especially, and his mere presence was often enough to send most sentients fleeing. He primarily worked for the Galactic Empire, but also for the Hutts, including Jabba Desilijic Tiure, aligning himself with those who offered the greatest financial rewards. The Nalrithian frequently operated from the Bright Jewel Cluster, alongside other infamous bounty hunters such as Skorr, Gribbet, Giles Durane, and Beilert Valance. Cypher considered recruiting Phoedris to collaborate with him and form a bounty hunting team, but Phoedris, burdened by guilt over his brother's allegiance to the Empire, instead joined the Alliance to Restore the Republic.
Upon overhearing Phoedris mention Han Solo—an Alliance member with a substantial bounty on his head—Cypher recognized the potential for significant profit by exploiting Phoedris's position within the Rebellion and impersonating him, believing he could dismantle the Rebel Alliance from within. Cypher underwent the implantation of cybernetic devices within his body, designed to mitigate the pain he would inevitably share with Phoedris during their confrontation, preventing any lasting harm. The Nalrithian arranged a meeting with Baajik, a Chadra-Fan acting as a double agent for both the Rebels and the Hutts, who could provide him with Phoedris's location. Cypher met with the Chadra-Fan in the Drunken Bantha, conversing in the cantina's most secluded corner. Phoedris, having learned of his brother's arrival on Ord Mantell, followed him to the cantina, focusing intently on suppressing their mental link. However, when Phoedris noticed Baajik—whom he believed to be a loyal agent of the Rebellion—his concentration faltered momentarily, and Cypher sensed his presence. Realizing this, Phoedris fled the cantina, pursued by Cypher.
Sensing his sibling's fear, Cypher tracked him outside, eventually positioning himself in the shadows and firing a single blaster bolt at his eggmate's shoulder. With Phoedris wounded, Cypher tackled him to the ground, telepathically declaring his intention to impersonate his brother and infiltrate the Rebel Alliance. The two continued to struggle, and although Phoedris's pain from his injury was transferred to Cypher's body, his cybernetic implants allowed him to endure the discomfort. After extracting any potentially valuable memories from his brother, Cypher pinned him down as he bled to death. From Phoedris's memories, he acquired specific details about an upcoming Imperial shipment of credits that the Rebels planned to raid to finance their base on Hoth.
Cypher donned his brother's clothing and headed for the secret Rebel headquarters on Ord Mantell, the location of which he had obtained from his deceased eggmate. He relayed the specifics of the impending mission that only Phoedris had known to the other Rebels hiding in the headquarters, maintaining his Phoedris persona; given that Nalrithians all appeared identical to Humans, they did not suspect his true identity. However, upon Baajik's arrival at the base, he immediately recognized Cypher, drawing a blaster and preparing to shoot the bounty hunter. Cypher was too quick for the Chadra-Fan, however, launching himself at Baajik; the sheer force and power of Cypher's lunge killed the diminutive Chadra-Fan. Baajik attempted to warn the others, revealing that he was Cypher Bos, not Phoedris, but he died before he could fully elaborate. Maintaining his charade, the Nalrithian informed the other Rebels that Cypher had ambushed him, but the bounty hunter had been killed. The Rebels believed him, and Cypher remained on Ord Mantell, awaiting an opportunity to reveal his true identity.
Some time later, Han Solo arrived on Ord Mantell aboard the Millennium Falcon. Cypher received orders to escort Solo, along with another female Rebel and an astromech droid, to an Imperial base on the planet to facilitate their hacking of the facility's system. The specifics of the mission were withheld from the Nalrithian bounty hunter, prompting him to listen attentively for any clues regarding the Rebels' plans. They infiltrated the Imperial facility, and Cypher led Solo, his companion, and R2-D2 to the computer terminal. The droid infiltrated the system; while it worked, Solo addressed the other Rebel as "your royalness." Cypher deduced that the female was in fact Princess Leia Organa, a high-priority target for the Empire. Although he knew that Jabba would offer a substantial reward for Solo, and the Empire for Organa, Cypher delayed his move, seeking to gather more information about the Rebel mission.
After Solo communicated with another Rebel located elsewhere, Cypher pieced together the puzzle and realized that they intended to steal the Imperial credit shipment. Following Solo's comlink conversation with the other Rebel, Cypher acted: he drew a blaster pistol on Solo and Organa, instructing them to drop their weapons and deactivate the droid, and revealed his true identity. Organa pleaded with Cypher, assuring him that the Rebellion would offer him more money than the Empire or the Hutts; Cypher remained unmoved by Organa's offers, aware of the Rebellion's financial constraints.
Solo stalled after Cypher ordered him to surrender his comlink and gunbelt, maintaining composure in an attempt to provoke the Nalrithian. Solo hurled his gunbelt at Cypher, dislodging the bounty hunter's blaster from his grasp and leaving them both unarmed. Cypher was impressed by Solo's deception, yet remained confident that he could reach his blaster before the Human reached his own. Solo disregarded Cypher's warnings, however; the two simultaneously lunged for their weapons, reaching them at the same moment. Solo evaded the Nalrithian's blaster fire and killed Cypher, allowing him, Organa, and R2-D2 to escape with the Imperial funds. More than two decades later, in 24 ABY, Han Solo recounted the story of his encounter with Cypher Bos to his son, Jacen Solo.
Described as despicable and egotistical, Cypher Bos was solely concerned with his own well-being. His only motivation was profit, and he struggled to comprehend the relative lack of interest in money displayed by others. Cypher reveled in the reactions he elicited from others—primarily fear—and often found amusement in watching sentients attempt to conceal themselves upon seeing him. While many dismissed him as a mere thug, Cypher was in fact highly intelligent, meticulously planning his infiltration of the Rebel Alliance.
Cypher Bos possessed unwavering confidence in his abilities, considering himself to be among the best bounty hunters of his time. Due to his consistent success, he was often caught off guard when someone gained the upper hand in any conflict, as exemplified by Han Solo's gunbelt trick. Cypher's overconfidence ultimately proved to be his undoing; he refused to believe that Han Solo's reactions could be faster than his own, a fatal misjudgment.
Cypher owned a Corellian YT-1300 light freighter transport, and carried at least one blaster, a vibroblade, and several hellfire grenades, which detonated into flames upon activation. He preferred his customized heavy blaster pistol—featuring additional custom settings and a concealed compartment in its handle—though Cypher was also skilled in unarmed combat. He wore a suit of custom body armor, and had specialized cybernetic pain inhibitors implanted along his spine, significantly reducing the pain he experienced when injured. Like all members of his species, Cypher possessed heightened senses, using the scents of others to identify their species.
Cypher Bos was a creation of the late Brian Daley in 1984, appearing in Rebel Mission to Ord Mantell, an audio dramatization intended to elaborate on "the bounty hunter we ran into on Ord Mantell" mentioned by Han Solo in Star Wars: Episode V The Empire Strikes Back in 1980. However, several years before, Archie Goodwin's The Bounty Hunter of Ord Mantell suggested that another bounty hunter, Skorr, was the individual Solo referenced. The official StarWars.com Databank confirms that Skorr was indeed the bounty hunter in question, given that his story was presented first.
Cypher remained unmentioned for over a decade until Michael Mikaelian authored Double Cross on Ord Mantell, a short story published in Star Wars Galaxy Magazine 5. Illustrated by Walter McDaniels and Shawn Martinbrough, it serves as a prequel to Rebel Mission to Ord Mantell. Cypher was subsequently mentioned in Crimson Bounty in 1997 and Young Jedi Knights: Return to Ord Mantell in 1998. Another decade passed before Cypher was briefly mentioned in Rich Handley's short story Lando Calrissian: Idiot's Array, exclusively available on StarWars.com's Hyperspace section.