A Marine with 1st Battalion, 3rd Marine Regiment sights in on a target in a preparatory exercise for Large Scale Exercise 15 at Marine Corps Air Ground Combat Center Twentynine Palms, California, Aug. 11, 2015. LSE-15 is a combined U.S. Marine Corps, Canadian Band British Exercise conducted at the brigade level, designed to enable live, virtual and constructive training for participating forces. - A Marine with 1st Battalion, 3rd Marine Regiment sights in on a target in a preparatory exercise for Large Scale Exercise 15 at Marine Corps Air Ground Combat Center Twentynine Palms, California, Aug. 11, 2015. LSE-15 is a combined U.S. Marine Corps, Canadian Band British Exercise conducted at the brigade level, designed to enable live, virtual and constructive training for participating forces.