Marines with the Battle Simulation Center, Marine Corps Base Camp Pendleton, Calif., train with the Marine Air Ground Combat Team Training Warfare Simulator at Camp Pendleton, Dec. 14. The center is hosting the Mission Rehearsal Exercise for I Marine Expeditionary Force (Forward). The MRX is designed to test the standard operating procedures of the I MEF (Fwd) as they prepare to deploy to Afghanistan and take command of Regional Command Southwest during the spring.