Simo Häyhä, a Finnish farmer turned sniper, is credited with at least 500 confirmed kills during the Winter War—the highest number for any sniper in a major war. He achieved this in less than 100 days, in temperatures as low as -40°C. Known as the 'White Death,' Häyhä used a standard bolt-action rifle without a telescopic sight. He preferred iron sights because they didn't fog up in the cold and didn't reflect sunlight, which would give away his position. He even kept snow in his mouth to prevent his breath from steaming in the frozen air. He survived the war and lived to the age of 96.