Sketch was a member of the clone trooper forces and fought for the Grand Army of the Republic throughout the Clone Wars. In the course of the Battle of Christophsis, Clone Commander Cody and Clone Captain Rex launched an inquiry into a potential Separatist spy within their own forces. They discovered an unusual signal in outgoing communications that led back to Clone Sergeant Slick and the area where he and his men lived. Thinking that a trooper under the sergeant's command might be the infiltrator, the clone officers ordered the squad to return to their living space for questioning. Sketch and Punch corroborated each other's stories, stating they were both in the dining area. Ultimately, Slick was exposed as the spy, but he managed to get away after causing significant damage to the armory. Slick was eventually captured.