Candidates for the Snow Serpent unit are screened for optimum strength, endurance and motivation, and then subjected to a grueling and dangerous training program with over a 50% drop out rate. In order to graduate, trainees must complete a Halo jump in a blizzard, ski cross country fifty miles carrying a hundred pound pack, hit over 95% of pop-up targets on the combat range and swim a hundred meters in freezing water while carrying fifty pounds of ammunition. Snow Serpents operate in conditions in which less hardened troops would hunker down and wait for a break in the weather. If they could enter the biathlon, they would sweep the event hands down. On the downside, they get listless and complacent in warm weather.