Stratagem of Running Away 
Bi Zaiyu was a famous general who resisted the Jurchen (Jin) forces during the late Southern Song period. He was immensely strong, able to draw a bow weighing over 200 jin (approximately 100 kilograms). The emperor summoned him and gifted him a fine suit of armor.
Due to the continuous invasion by the Jin forces, in the second year of the opening ceremony of the Southern Song Dynasty (1206 AD), Bi Zaiyu was ordered to fight against the northern invaders. His first task was to recapture Hezhou City (now located northeast of Dangtu County, Jiangsu Province). 
When the Jin soldiers received news that Bi Zaiyu was leading his troops to attack, they transported many wooden and stone materials to strengthen the city gates and defenses. However, Bi Zaiyu did not attack the city head-on but used a clever strategy to outwit the enemy.
Bi Zaiyu ordered his subordinates to lead the navy, hoist flags on the warships, and display weapons to create a grand spectacle. The Jin soldiers believed that the Song army was planning to attack from the west through the waterways, so they focused their defenses there. 
Unexpectedly, Bi Zaiyu led his main force to move silently to the eastern side of Hezhou City. They launched a sudden attack from the southeast corner of the city, quickly capturing it and killing many Jin soldiers, forcing them to flee. 
The court intended to promote Bi Zaiyu to the position of imperial historian, but he declined, saying, ‘There are 81 provinces south of the Yellow River. I have only recovered one province. How can I accept a promotion?’ 
Later, the Jin soldiers attempted to cross the Huai River from Liuhe (north of present-day Nanjing) to invade southwards. Bi Zaiyu was ordered to lead his troops and horses to Liuhe to resist the Jin soldiers and prevent them from crossing the Huai River. 
At that time, the Jin soldiers had a significant advantage. To defeat the enemy, Bi Zaiyu ordered his troops to feign retreat and lure the Jin soldiers to exhaust themselves. The archers were hidden on the walls of Liuhe, waiting to ambush the enemy. 
Seeing no movement inside the city, the Jin soldiers boldly approached the city gates. When the enemy reached the city walls, Bi Zaiyu gave the order, and thousands of arrows were fired, killing many Jin soldiers. 
The Jin soldiers were suddenly attacked and their formation fell into chaos. The soldiers of Liuhe city took the opportunity to blow the battle horn and raise their flags, scaring the Jin soldiers into a hurried retreat.