LtCol Kier was again ordered overseas in May 1944 to serve as the operations officer and executive officer for Marine Aircraft Group 13 (MAG-13) in the Marshall Islands. He detached from MAG-13 on 15 September 1944 in order to serve as an observer with the Amphibious Group 3 Air Support Control Unit during the Battle of Leyte. On November 1, 1944, he joined Colonel Vernon Megee as a member of the newly formed Provisional Air Support Command, whose role was to organize, train and equip Marine units to duplicate the air control function of the navy but do it ashore. He served with Landing Force Air Support Control Unit 1 (LFASCU-1) at both Iwo Jima and Okinawa. During the Battle of Okinawa, he was the commanding officer of LFASCU-1. For meritorious service on Okinawa from May 15 to June 21, 1945, he was awarded the Bronze Star Medal with Combat "V". He remained with LFASCU-1 through the end of the war and rotated back to the States in August 1945.