A snow cave will keep you going in extreme winter conditions.
Every kid in the northern U.S. and Canada probably built a snow cave at one time or another just for fun, and those who did can remember how surprisingly warm it was once out of the wind.
Watch this short tutorial on the construction of a snow cave, it may well come in handy for the hunter and outdoorsperson.
Snow caves are a practical survival shelter and actually taught as common practice for many mountain and winter camping courses, not just for survival, but as a standard bivouac method in the wilderness.
A good snow cave and even just one candle will trap enough heat to keep you alive in a survival situation so keep this skillset in mind when hunting, snowmobiling, or heading out into austere wilderness conditions. Ensuring you always have a basic survival pack with the essentials and you will be able to sustain for at least a couple of days if there is an emergency.