180531-M-PK127-004 PACIFIC OCEAN (May 31, 2018) Logistics Specialist 3rd Class Zefeng Guo, assigned to the Essex Amphibious Ready Group (ARG), unholsters his weapon during a live-fire exercise aboard the Wasp-class amphibious assault ship USS Essex (LHD 2) while underway in the Pacific Ocean, May 31, 2018. The Essex ARG and 13th Marine Expeditionary Unit (MEU) are conducting Composite Training Unit Exercise (COMPTUEX), the final exercise before the units' upcoming deployment. This exercise validates the ARG/MEU team's ability to adapt and execute missions in ever-changing, unknown environments. Upon completion of COMPTUEX, the 13th MEU and Essex ARG will be certified as the nation's premier forward-deployed, crisis response force, capable of executing missions across the broad spectrum of military operations. (U.S. Marine Corps photo by Cpl. Francisco J. Diaz Jr./Released)