Sienn Sconn was a male Human thief of the male persuasion, originally from Ryvellia located within the Avhn-Bendara system.
At the young age of seven, Sienn experienced the tragic loss of both his parents. They were killed by Imperial operatives during the Ryvellia uprising in Ryvellia's capital. During the unrest, the Empire unleashed a barrage of turbolaser fire upon the dissidents. The devastating attack obliterated much of Sienn's neighborhood and resulted in the deaths of countless residents.
This event ignited an unquenchable animosity towards the Empire within Sienn. Subsequently, he was taken in and raised by his uncle, the renegade Cryle Cavv. Cavv imparted the skills of thievery to Sienn, who eventually excelled and became recognized as one of the most skilled master thieves. Sienn frequently employed a variety of specialized equipment provided to him by his uncle.
Having received a moral education from his uncle and possessing a well-developed sense of ethics, Sienn selectively targeted excessively wealthy individuals and organizations, crime lords, and, naturally, members of the Empire. While not formally associated with the Rebel Alliance or the New Republic, Sienn occasionally collaborated with them in their efforts against the Empire.
During his time on Venaari, Sconn found himself with little work and spent most of his time at the Binary Bar, consuming copious amounts of Venaarian Cringe-Ale. He considered stealing the Mobquet Nebulon-R Racer showcased in the cantina to generate enough credits to settle his debts with his landlord. However, his plans were disrupted by the arrival of Shandria L'hnnar, a New Republic agent. Intrigued by her presence, Sconn was about to approach her when a young Venaarian man burst into the bar and was fatally shot by pursuing stormtroopers. Sconn intervened, preventing the stormtroopers from harming L'hnnar by engaging them with his stun-staff. He attempted to discreetly escort her out of the back of the bar, but their path was blocked by another group of stormtroopers. L'hnnar discovered a vent leading to the roof, and the two ascended to the rooftop. The thief leaped into the alley below and neutralized the crew of a Venaarian Strike Speeder, which he and L'hnnar then used to make their escape.
They made their way to the Ven-Kavi Starport so L'hnnar could return to her ship and leave the planet. During their journey, they were intercepted by Pentix Graphyt, a bounty hunter. Sconn climbed onto the speeder's roof to confront the bounty hunter, but he was quickly outmatched. He managed to fire his wrist laser, damaging the coolant tank of Graphyt's rocket pack. As the bounty hunter struggled to remove the malfunctioning rocket pack, Sconn attached several explosives to him and launched him towards a blockade outside the starport.
Upon reaching the docking bay where L'hnnar's ship was located, Sconn declared that he would hold off the Imperials to allow her to escape. She attempted to persuade him to join her and the New Republic, but he refused to relinquish his independence. He seized control of the mounted heavy blaster cannon on their speeder and opened fire on the approaching security forces. The Imperials destroyed Sconn's speeder, knocking him to the ground. He then spotted a locked access panel leading to the starport's underground maintenance tunnels. He eluded the Imperial forces led by Major Gaevril Daraada. As he returned to his apartment, Sconn discovered a cred stick in his pocket, a gift from L'hnnar. He used the 25,000 credits on the stick to settle his debts with his landlord and enjoy a relaxing evening.
Sconn found himself on Rydonni Prime, disguised as a servant, in order to infiltrate Rilvvan K'ntarr's mansion during a social gathering. He had been contracted by Draskha, a Hutt, to pilfer a prototype weapon.
The thief intended to gain entry to the Rythani Products Building and abscond with the prototype weapon that was scheduled to be presented to Moff Caerbellak during a celebratory parade. After excusing himself from the party, Sconn was seized and pulled into a side room by Princess Kalieva K'ntarr, who embraced him passionately. Upon realizing that he was not the person she expected, she threatened to alert the guards. Sconn calmed her down and assessed the windows for a possible escape route. Discovering that the windows were equipped with Type VII SafeScreens sensor alarms, Sconn paused to reconsider his strategy. During this time, the Princess questioned him and correctly surmised that he was there to steal the prototype. Desiring a way to leave the planet, she offered to assist Sconn in gaining access to the lab and stealing the weapon.
Sconn accompanied her to Prototype Lab A, where the princess attempted to gain entry. When the guards intervened, she created a diversion, allowing Sconn to disarm and incapacitate them. He then restrained K'ntarr and confined her to a storage closet so he could proceed with his theft. He entered the lab and subdued a group of stormtroopers. Sconn located the prototype encased in a sphere of blast-shield durasteel and used a repulsorsled to load it onto an AT-AT designated Unit 718-A. Before he could leave the lab, K'ntarr, who had escaped her confinement, surprised the thief. She pleaded with Sconn to take her with him. He reluctantly agreed and instructed her to board the walker.
After departing the facility, Sconn received a communication from Imperial command, questioning the AT-AT's unauthorized departure. He bluffed, claiming to be part of a maintenance crew conducting a performance evaluation of the vehicle before the Moff's parade. As he piloted the walker towards his rendezvous point with the freighter he had hired for his escape, the walker malfunctioned and came to a halt. Sconn repaired it, but the process took several hours. The thief resumed his journey to the meeting location and found himself caught in the middle of the parade being held in the Moff's honor. Sconn convinced the other Imperial forces that he was authorized to be there and joined the ranks of Imperial walkers. He planned to proceed down the street past the assembled dignitaries and reach his escape ship.
However, Moff Caerbellak was informed of the prototype's disappearance and declared martial law on the planet. K'ntarr witnessed her father being threatened and implored Sconn to intervene. The thief activated the loudspeaker and addressed the dignitaries. He informed the Moff that he had stolen the prototype and then destroyed the legs of the reviewing stand, causing it to collapse. He resumed his escape in the walker but detected a noise in the back. Entrusting control to K'ntarr, he went to investigate and was ambushed by Variise, Moff Caerbellak's personal bodyguard from the Mistryl Shadow Guard. During the ensuing fight, he forced her onto the assault ramp, which he then detached from the walker using one of his thermal explosives.
Returning to the cockpit, he was informed by the princess that the fight had damaged the drive units, rendering the walker unable to steer or slow down. The walker careened through the crowds watching the parade, although Sconn provided them with sufficient warning to evacuate. The walker continued its uncontrolled trajectory, heading towards a starscraper housing the Rydonnian Imperial Consulate. Sconn swiftly secured the repulsorsled carrying the prototype weapon to a speeder bike using magnalock grapplers. Sconn and the princess ejected from the walker just as it collided with the building and reached the rendezvous point to meet the ship he had chartered. The princess had a change of heart and decided to remain on the planet, so Sconn boarded the Ghtroc freighter Corellian Thunder and departed the planet to deliver the prototype to Draskha and receive his payment.
He was instrumental in the capture of the Executor-class Star Dreadnought named Guardian.
Sconn carried a stun-staff that could be collapsed or extended up to two meters. He also possessed a wrist laser gauntlet and frequently made use of thermal half-spheres.