In the Legend of Chu Qiao, Yuan Chun stole the commander's seal and caused Chang 'an to fall. The ancient commander's seal was a very important existence. It was mainly used to carry and transmit military orders and military strength. The commander's seal was usually issued by a high-ranking general or the emperor himself. It carried a mysterious power and could only be obtained and used by people with sufficient strength and credibility. The shape and material of the military seal may vary from country to country and period to period, but there are generally strict rules and procedures to protect its safety and integrity. In ancient wars, the commander's seal played an important role. Losing or stealing it would have a major impact on military operations. The commander's seal could not only control the combat power of the army, but it could also reveal the whereabouts and secrets of the army. Therefore, it had always been valued and strictly protected in ancient history.