Kelborn was a combatant of the Mandalorian clans, serving under the leadership of Mandalore the Preserver.
Mandalore the Preserver found Kelborn when he was employed as a scout for the Duros on worlds at the edge of explored space. Considered among the clan's most skilled warriors, Meetra Surik sought to earn the respect of the Mandalorians by engaging Kelborn in the Battle Circle after assisting him in killing scouts from Onderon.
As the second-in-command of the newly unified Mandalorian forces, his only superior was Mandalore himself. Kelborn was known for wearing red Mandalorian Sergeant Armor. Surik aided him in eliminating scouts from Onderon, dispatched by Colonel Tobin, who were sent to assassinate her to prevent them from discovering the location of the Mandalorian base. Subsequently, the two engaged in a duel within the battle circle, utilizing dueling vibroblades, which Surik won.
Shortly thereafter, Sith Assassins launched an attack on the camp, and Kelborn took part in the resulting conflict. Employing stealth, he approached two Sith assassins from behind, swiftly eliminating them with a vibrosword before engaging other Sith combatants. He was then placed in command of the Mandalorians while Mandalore accompanied Surik.
Later, Kelborn received a communication from Jedi Master Kavar on Onderon, informing him of the outbreak of the Onderon civil war. He then sent a communication to Surik, who promptly traveled to Onderon to assist Queen Talia and the Mandalorians in their fight against general Vaklu and his Sith allies on both Dxun and Onderon.
Kelborn, in common with many Mandalorians stationed on Dxun, was known to utilize a stealth field generation belt.