A U.S. Marines attached to C Company, 1st Battalion, 3rd Marine Regiment, "The Lava Dogs" throws a M67 Grenade into trenches during a company assault at Lava Viper aboard Pohakuloa Training Area, Hi., Jun. 9, 2015. C Company assault is there final exercise of Lava Viper which includes vehicles and air assets. (U.S. Marine Corps photo by Cpl. Ricky S. Gomez/Released)