A Belugan male of significant rank, Major Rigosso, served as a military officer within Lord Otua Blank's military force on the planet Quarzite. The year 20 BBY saw the Belugans abduct Pluma Sodi, a Kage female, intending to deliver her to Blank for the dictator's personal desires. Aware of the impending threat of a rescue attempt by Kage Warriors that could jeopardize the mission, Rigosso contracted a team of six bounty hunters to safeguard Sodi and ensure her secure arrival at Blank's stronghold.
Rigosso greeted the bounty hunters at the planetary turbolift, a transport system that took Quarzite visitors beneath the planet's high-pressure surface; subsequently, the Belugan major briefed the group on the mission's details and potential hazards. Once underground, the squad traveled via subtram, encountering an assault by Kage Warriors during their journey. Following an extended conflict between the two sides, Krismo Sodi, Pluma's brother, killed Rigosso.

Rigosso, a Belugan male native to the planet Quarzite, held the military officer position of major and served the Belugan dictator Lord Otua Blank during the Clone Wars, a galactic conflict between the Galactic Republic and the Separatists. In 20 BBY, a conflict arose between the Belugans and the Kage, two native species on Quarzite. The Kage Warriors, an elite fighting force, were known for raiding Belugan subtrams, and Rigosso's elite troops were ineffective against them. At one point, the Belugans abducted Pluma Sodi, a Kage female, intending for Blank to take her as his bride.
However, recognizing the Kage Warriors' superior combat skills compared to Blank's soldiers—who would likely intercept Sodi's escort—the Belugans sought external assistance. Rigosso enlisted a team of six bounty hunters, led by the rising hunter Boba Fett, for a fee of 600,000 credits to come to Quarzite. Initially, the bounty hunters were unaware that their assignment involved protecting Sodi from Kage rescue attempts.

Given Quarzite's highly pressurized atmosphere, Rigosso met the bounty hunter team—Fett, Bossk, Latts Razzi, C-21 Highsinger, Dengar, and Asajj Ventress—at a space station situated outside the planet's atmospheric boundary. This station featured a massive turbolift that descended beneath Quarzite's surface, where the Belugans and Kage resided. Rigosso introduced himself and briefed the team on the mission's objectives via a holographic display, providing information about the Kage, Blank, and Quarzite's unique atmospheric conditions. Despite the bounty hunters' inquiries about their cargo, the major tersely warned them that failure to deliver it safely would incur Blank's wrath.
During their ride in the turbolift, Rigosso and Fett further discussed the mission, with the Belugan eventually revealing their destination as Blank's stronghold. Sodi was confined within a wooden container for the journey, which Rigosso strictly forbade opening. Sodi was placed in a passenger car alongside Rigosso, while the hunters dispersed throughout the tram accompanied by two Belugan guards. As the Belugans anticipated, the subtram was attacked by Kage Warriors riding milodons shortly after departing.

The acrobatic Kage Warriors swarmed aboard the train, and Rigosso joined the bounty hunters in fighting them, firing his weapon at two warriors and physically striking another. The major identified Krismo Sodi, Pluma's brother, as their leader to Razzi, before positioning himself in front of Pluma's container as the final defense. With the bounty hunters engaged, Rigosso confronted Krismo, resulting in him being killed by Krismo's electro swords, his body falling to the subtram floor. Ultimately, Ventress, experiencing a change of heart, allowed Krismo and Pluma to escape in exchange for money, rendering Rigosso's mission unsuccessful.

Rigosso, holding the rank of major, was a devoted follower of Otua Blank, faithfully executing his master's commands. He spoke of Blank with reverence, often referring to him as "my lord." While courteous to the bounty hunters, he disapproved of their curiosity about the cargo and threatened them with punishment should they fail to deliver it safely.
Rigosso's concern for Pluma Sodi's well-being stemmed solely from Blank's desire for a healthy bride. Despite his welcoming demeanor, Ventress sensed urgency in Rigosso's greeting, suggesting he was in a hurry. Rigosso was prepared to sacrifice himself to protect Blank's cargo, mocking Krismo's intention to rescue his sister. The major possessed orange-and-gray-colored skin and white eyes featuring black, star-shaped irises.
The Belugan demonstrated his combat abilities by effectively using a blaster pistol to defeat several Kage Warriors during the subtram conflict. He remained in the fight longer than most of the Kage combatants before ultimately being defeated by Krismo.
Rigosso wore a brown military uniform, including a fitted bodysuit, a two-piece breastplate, boots, shoulder pads, and gauntlets with gloves that had metal claw tips. Each gauntlet had a pistol holster, one of which held his silver blaster pistol when not in use. His uniform featured white, ribbed patches, and his left breastplate displayed a black-and-yellow Belugan emblem. While similar to the uniforms worn by Belugan soldiers, Rigosso's lacked some armor elements.

Rigosso made his debut in "Bounty," the twentieth episode of Star Wars: The Clone Wars' fourth season, which aired on March 2, 2012. Tom Kane provided the voice for Rigosso in the episode. Darren Marshall created concept artwork of the character, although StarWars.com initially referred to the character as "Rigossa." The Belugans' four-part mouth design was inspired by existing mouth structures and the baleen of a whale, the fringed plates whales use to filter food from water.