The flagship winter tire for Continental is their ExtremeWinterContact. It is a fantastic tire that provides grip in both deep snow and icy conditions.
Its high-density sipes allow this tire to bite very well in deep snow conditions while keeping contact with the road's surface. This gives you, the driver, better grip.
After having tested this tire versus its main competition (Bridgestone Blizzak WS70 and Michelin X-Ice Xi2) I consider this to be a very competitive option.