Zhu Ran
In 223, Cao Pi ordered Cao Zhen, Xiahou Shang, Zhang He and others to lead Wei forces to attack Wei's rival state, Eastern Wu, while he personally stationed at Wan (宛; in present-day Nanyang, Henan) to provide backup. The Wei forces attacked and besieged Jiangling (江陵; present-day Jiangling County, Hubei), which was defended by the Wu general Zhu Ran and some 5,000 soldiers. The Wei forces managed to defeat Wu reinforcements led by Sun Sheng (孫盛), Pan Zhang and Yang Can (楊粲), who were trying to help Zhu Ran. During the siege, Cao Zhen ordered his troops to dig tunnels, pile up earth to form small mounds, and build watchtowers to rain arrows on the defenders in Jiangling. Zhu Ran and his men managed to hold their ground and even found a small opportunity to counterattack and destroy two Wei camps. After some six months of siege, the Wei forces could not breach Jiangling's walls so they retreated.