The survivalists are in Dallas' territory: dog mushing. Dallas and the rest of the Endurance athletes are the first to arrive and harness their team of dogs. Not familiar with dog mushing and not wanting to waste any time, the Military team skips the dogs altogether and walks. The mission? Race across a 30-mile stretch of treacherous glacier, plunge down a 2,000-foot gully and battle 15 miles of whitewater rapids to the extraction point in Berners Bay.