War elephants are weapons of brute strength. Their task is to charge the enemy, trampling soldiers to death and panicking their horses. (Horses generally hate elephants on sight.) War Elephants saw use in India until the 19th century, when cannon and rapid-fire machine guns rendered them far too vulnerable. The first European to meet these behemoths in battle, Alexander the Great encountered war elephants during his destruction of the Persian Empire. He was so impressed by the beasts that he incorporated some into his own army. It is said that Alexander was discouraged from driving into India partly because the enemy there had thousands of war elephants on hand, far too many for his forces to take on.