I was once approached by a polar bear. I only had a pistol loaded with blanks to defend myself. Fear caused a small droplet of sweat to form on my forehead, it immediately froze. I took the droplet and put it in the pistol. Then I fired at the bear. The heat from the gun melted the sweat droplet. The droplet then re-froze due to the extreme cold and struck the bear in the head. The droplet then melted from the bear's body heat.
The bear died anyway… from water on the brain.