Trapper was a member of the clone trooper ranks, fighting for the Grand Army of the Republic during the period known as the Clone Wars. Alongside Jedi General Mace Windu, Clone Commander Ponds, and a clone nicknamed "Hawkeye," Trapper saw action on Malastare, where they encountered the creature called the Zillo Beast. Later, as a member of the 212th Recon Division, he fought alongside Jedi General Obi-Wan Kenobi, Clone Commander CC-2224 "Cody," "Boil," and "Waxer" during the events of the Second Battle of Geonosis.
During the year 21 BBY, Trapper served under the command of Clone Commander "Ponds" during the Battle of Malastare. Following the successful testing of the experimental superweapon known as the electro-proton bomb, Trapper was part of a search party that included Ponds, Jedi Master Mace Windu, and the clone trooper Hawkeye, tasked with assessing the aftermath of the battle. They came across the Zillo Beast, and Trapper, along with Ponds and Windu, managed to escape after Hawkeye was killed.
Trapper was a part of the 212th Recon Division during the Republic's second offensive on the planet Geonosis. He was deployed alongside Jedi General Obi-Wan Kenobi; however, while en route to Point Rain, their gunship was shot down. Trapper and Kenobi were the only ones to survive the crash, eventually being rescued by troopers Boil and Waxer, allowing them to rejoin the fighting.
Trapper's first appearance was in the Star Wars: The Clone Wars episode titled "The Zillo Beast," which was broadcast on April 3 in the UK and on April 9 in the USA, both in the year 2010. As with all clone troopers featured in the series, his voice was provided by Dee Bradley Baker. The name "Trapper" is a reference to the character "Trapper" John McIntyre from the television series MAS*H.