Marines with 4th Medical Battalion, 4th Marine Logistics Group, Marine Forces Reserve, carry a casualty in a mass heat casualty exercise during the 4-15 Integrated Training Exercise aboard Marine Corps Air Ground Combat Center, Calif., June 20, 2015. During the mass heat casualty exercise, Marines and sailors faced a situation where multiple casualties were rapidly brought into the medical station, and Marines and Sailors had to work together efficiently to ensure that all casualties were assessed and treated properly. - Marines with 4th Medical Battalion, 4th Marine Logistics Group, Marine Forces Reserve, carry a casualty in a mass heat casualty exercise during the 4-15 Integrated Training Exercise aboard Marine Corps Air Ground Combat Center, Calif., June 20, 2015. During the mass heat casualty exercise, Marines and sailors faced a situation where multiple casualties were rapidly brought into the medical station, and Marines and Sailors had to work together efficiently to ensure that all casualties were assessed and treated properly.