Marines and corpsmen with the 11th Marine Expeditionary Unit transport role players acting as injured patients as part of a mass casualty training exercise during Certification Exercise (CERTEX) at Camp Pendleton, California, June 15, 2014. CERTEX serves as the final at-sea period for the 11th MEU and Amphibious Squadron 5. It is designed to strengthen the blue-green team's ability to operate together and to respond to various situations while deployed. (U.S. Marine Corps photo by Lance Cpl. Laura Y. Raga/Released)