Harrison and 30th Division returned to the front lines following the launch of German massive offensive in Ardennes on December 17, 1944 and participated in combat in Malmedy-Stavelot area. Hobbs tasked Harrison with the command of the Task Force, consisting of 119th Infantry Regiment, which later repelled German assault at La Gleize. Harrison and his task force destroyed or captured 178 enemy armored vehicles, including 39 tanks.