During the Clone Wars, a male Ithorian bounty hunter named Onca operated alongside his brother, Bulduga. The reputation of Onca and Bulduga attracted the attention of both Count Dooku, a Sith Lord, and Moralo Eval, a Phindian criminal mastermind. These two extended an invitation to the brothers to compete in a series of trials at the Box, located on the planet Serenno. With Bulduga's untimely demise before the challenges even began, Onca was left to compete on his own.
At some point in their past, Onca and his brother, Bulduga, embarked on careers as bounty hunters, creating a renowned partnership that garnered them galaxy-wide fame. In 20 BBY, amidst the Clone Wars, Count Dooku, the Sith Lord, and Moralo Eval, the Phindian criminal genius, invited the brothers, along with other bounty hunters, to participate in a series of challenges held at the Box on the planet Serenno. It was their impressive reputation that initially caught eye of Dooku.
Bulduga's involvement in the tournament was abruptly ended by Cad Bane, a Duros bounty hunter, who murdered him shortly before the competition began. This act stemmed from a disagreement regarding Bulduga's fedora. Bane inquired about the hat's origin, prompting Bulduga to draw his weapons, sensing the escalating tension. However, Bane was quicker, fatally shooting Bulduga and seizing his fedora. Onca witnessed this, but fear of Bane's superior skills prevented him from retaliating. He secretly grieved his brother's death.
The bounty hunters were competing in potentially lethal challenges, with the prize being the opportunity to kidnap Supreme Chancellor Sheev Palpatine of the Galactic Republic. Onca, like the others, performed well in the initial challenge. However, due to Embo's actions, he nearly plunged to his death into the Dioxis gas-filled room, but he managed to survive and advance to the second challenge. Upon entering, they discovered the room was filled with electrified laser blade columns. One of these columns nearly struck Onca's head after Rako Hardeen pushed Jakoli to safety, but Onca dodged to avoid it. Soon after, Onca found himself trapped by the columns, with one moving directly towards his head, its laser dangerously close to his face. Fortunately, the laser stopped short and retracted. Relieved, Onca sighed, but before he could react, he was impaled from behind by another laser blade, resulting in his death and making him the first casualty of the challenges.
Onca, an Ithorian male, stood at a height of 2.05 meters, equivalent to 6 feet and 9 inches. He possessed brown eyes and skin of a brown hue.
Alongside his brother, Bulduga, Onca was a member of a renowned and successful bounty hunting team, known throughout the galaxy. In contrast to his brother, a quick-drawing gunslinger, Onca was slower, unable to overcome his Ithorian physique to draw and fire as quickly as Bulduga. This limitation ultimately led to the loss of his career and his life when he was fatally trapped at the Box on Serenno.
Onca prioritized firepower over elegance or showiness. He often carried multiple blaster rifles, including a shortened version, simultaneously. His arsenal included an EE-3 carbine rifle and a durable DLT-18 laser rifle.
Onca's first and only physical appearance was in "The Box", an episode of the television series Star Wars: The Clone Wars. He later appeared in a flashback sequence in the episode "Crisis on Naboo."