Zonka was assigned to Jerec's battle group during the Galactic Civil War. In 5 ABY the group invaded Ruusan and after the disappearance of Patrol 341 in the planet's desert, Zonka was among the complement of a AT-AT that was sent to investigate.
The walker was under the command of Dark Jedi, one of Jerec's apprentices who led the team from an AT-ST. The group left from and after scanning the Patrol's zone of authority, Yun directed them to a different area to the north where he believed its leader took them. Eventually the walkers reached a suspicious rock pile. A company of Stormtroopers disembarked with a pair of crawlers. Behind him, someone sprinted and dove behind a rock for cover; seeing that it was his Corporal Niko Smith, he nodded. Smith complained about the meticulous search over all this distance, and Zonka reminded him his salary and the Empire's "gratitude". Squad by squad, the troops fanned out into the stone-maze as Yun watched from the top of the Scout.
By 5 ABY Zonka was a grizzled officer.