FORT LEONARD WOOD, Mo. (Army News Service, April 20, 2012) -- The Best Sapper competition, a centerpiece of the Army Engineer School's annual regimental conference, kicked off in the dark, early morning hours April 19, with 38 teams of two participating, the largest field yet to compete.The active and reserve-component competitors will move through a course of 50 miles in 50 hours with a variety of obstacles in the way designed to exhaust them physically, mentally and creatively.In the way of earning the title of Best Sapper stand events such as helocasting into a lake with a packed rucksack, rappelling a 40-foot tower and 100-foot cliff, day and night land navigation problems, obstacles that need to be detonated, thermal breaching exercises and pushing through a gas-mask run.The final gut-check comes the morning of April 21 after the X-miles run, named so because the competitors have no idea of the run's length, it could be 4, 8, 12 miles or a distance in between.