In the first leg of the 13-leg competition, four teams battle their way to the summit of Mount Gerdine. To get there, they must cross a rapidly thawing lake, traverse a crevasse-filled glacier and claw their way up walls of crumbing ice. On the second leg of the competition, teams are dropped near the top of a towering mountain peak and provided with skis, snowboards and climbing rope. The mission is clear: Descend the mountain in any way possible.