In 279 AD, there was a rebellion in Liangzhou, and Emperor Wu of Jin ordered Malone to lead a crusade. In an ambush, Malone ordered soldiers to place a large number of magnets on both sides of a narrow passageway in advance, and ordered his men to take off their armor and put on rhinoceros armor, and then lured the enemy into the passageway. Because the enemies are wearing armor, attracted by magnets, complaining that the other side has magic help. But Malone's department was full of energy, killing at will and winning a great victory. This is an excellent example of China's ancient military use of magnets as secret weapons.