During the battle of Narva the Swedish army numbered 8,000 men (with another 2,500 garrisoned within Narva itself) against the Russian 34,000-40,000 men.
For most of the day a blizzard blew over both armies, forbidding attack on either side. But a change in the wind brought the full force of the storm, upon only the Russians.
Attacking in densely packed columns rather than the thin lines usually used, Charles XII directed an attack on the Russian line, the Caroleans, hidden by the storm were able to close the distance and bringing the full force of the Gå-På attack to bear routed the numerically superior Russian force.
Swedish deaths numbered only 600 with another 1,200 wounded.
Russian forces lost 9,000 dead and over 20,000 Russian soldiers were captured in the battle.
This was not the end of the Great Northern War but that's for later.