Members from each military branch sit and await further instruction at the "2015 Mangudai Warrior Challenge." The 58-hour event paired U.S. senior enlisted leaders with their Republic of Korea counterparts to accomplish different tasks through a range of scenarios while operating on limited food and sleep. The United States Forces Korea event held May 13-15, 2015, is in its second year. (U.S. Army photo by Staff Sgt. Mark A. Kauffman)