Niai Fieso, a con artist originating from Veterned on Troiken, had humble beginnings. Unable to secure stable employment, he wandered Veterned's streets until he joined Freon Drevan's criminal enterprise, working in a factory that produced fake Gasgano podracing merchandise. He was also given opportunities to deceive unsuspecting individuals, and his success impressed Drevan so much that Fieso quickly became the organization's most valued member. Together, Fieso and Drevan expanded into smuggling operations.
Growing weary of Drevan's leadership, Fieso orchestrated his downfall by informing the authorities, leaving Drevan with significant tax liabilities. Venturing out independently, Fieso thrived beyond Troiken, impersonating an agent of Gasgano. He attempted to defraud businesses in the Corporate Sector, but this soon attracted the attention of the Corporate Sector Authority. Forced to flee the Corporate Sector by the Security Police, Fieso sought refuge on the desolate planet of Tatooine. There, he found employment as a vendor at the Mos Espa Grand Arena during the Boonta Eve Classic in 32 BBY. Unbeknownst to Fieso, Drevan was in the audience, and a public altercation led to their imprisonment in jail, with Fieso subsequently transferred to the Corporate Sector Authority's jurisdiction.
Born into poverty in Veterned, the capital of Troiken, Niai Fieso's family could not afford to educate him. As a result, the young Xexto spent much of his childhood roaming the city's streets. Despite finding temporary work in various jobs, he eventually gravitated towards Veterned's criminal underworld. Fieso began working for the con man Freon Drevan, who operated a bootleg scheme that involved selling counterfeit merchandise supposedly related to Gasgano, a renowned podracer from Troiken.
Initially, Fieso's role in Drevan's organization was to manufacture the merchandise for Drevan to sell. He was also given opportunities to con unsuspecting people, and Drevan was impressed by Fieso's ability to deceive others with his charming personality. The young Xexto quickly rose through the ranks, becoming Drevan's most trusted confidant. Together, they expanded the organization beyond simple bootlegging and into the realm of smuggling, primarily dealing in illegal goods such as spice.
Eventually, Fieso grew tired of being under Drevan's command and began plotting to eliminate his superior. He started by diverting profits from their spice smuggling operation and then informed the authorities of Drevan's activities before fleeing the system. The ensuing raid resulted in Drevan's imprisonment, the revocation of his business license, and Fieso's freedom to pursue his own ventures. Drevan was also burdened with tax debts. Fieso achieved success as an independent con artist, defrauding unsuspecting individuals and businesses for substantial profits. One of his most lucrative schemes involved posing as Gasgano's agent.
Taking his business to the Corporate Sector, Fieso enticed businesses with "exclusive sponsorship deals" for Gasgano. The anticipated profits from this scheme would have secured the Xexto's retirement, but his actions drew the attention of the Corporate Sector Authority. One of the Authority's Attorney Generals exposed Fieso's deception, and the Xexto found himself pursued by Security Police. Evading capture, Fieso fled the sector with the few resources he had left.
To avoid further scrutiny, Fieso traveled to Tatooine, intending to lie low due to his limited funds. In the spaceport of Mos Espa, he found work as a food vendor, selling refreshments like gorgs at the Mos Espa Grand Arena during the Boonta Eve Classic in 32 BBY. Although the job was legitimate, Fieso saw the podracing crowd as an ideal target for his scams. While searching for potential victims, he was struck in the face three times by Drevan, who was among the spectators. A fight ensued between the two Xextos, leading to their imprisonment in jail. Subsequently, Fieso was transferred to the custody of the Corporate Sector Authority.
Niai Fieso possessed a warm and friendly demeanor, especially when relieving his targets of their credits. This characteristic helped Fieso rise to prominence in Freon Drevan's organization, allowing him to advance rapidly through the ranks. However, Fieso was ambitious and did not hesitate to deceive his own boss. He even betrayed Drevan to local authorities to operate independently. For a time, his skills brought him success as a con man, but when he attempted to take on the Corporate Sector, he found himself outmatched. Despite attempting to settle down and lie low, he still desired to swindle innocent beings, even while employed in a legitimate job.
The character of Niai Fieso made his first appearance, unnamed, in the DVD release of 1999's Star Wars: Episode I The Phantom Menace, in a scene that was not included in the original theatrical release, during the film's podracing sequence. In 2007, the character was identified and given a backstory by Sander de Lange, writing as "exarxan" through the StarWars.com Hyperspace feature "What's The Story?" De Lange created the character's name using anagrams of his friends' names, Iain and Sofie. In search of potential connections to the character, de Lange researched other existing Xexto in the Expanded Universe, identifying two suitable candidates: Tosinqas from HoloNet News Vol. 531 53, and Freon Drevan, identified in the "Coruscant Limited" set of the Star Wars Customizable Card Game. De Lange used Tosinqas in a second "What's The Story?" entry he submitted and connected Drevan to his Fieso story.
Drevan's card in "Coruscant Limited" mentioned a "partner" who scammed the character, leaving him with tax debt. de Lange retconned his character into that role. De Lange attributed the phrasing "right-hands Xexto" from the finished Databank entry to Timothy Carlsson, who helped refine the submission. De Lange linked the character to the Corporate Sector from Brian Daley's 1979 novel Han Solo at Stars' End, intending to have his character incarcerated in the Stars' End prison. The reference was removed from the final entry because it was chronologically before the prison existed.