Chapter 73 of Water Margins mainly told the story of Song Jiang and others gathering at Liangshan Lake to accept amnesty and attack Fang La. In this round, Song Jiang and the others analyzed the situation and realized that accepting amnesty was the only way out and formulated a plan to attack Fang La. They used the advantage of the navy in Liangshan Lake to coordinate with the internal forces of Liangshan Lake and finally successfully attacked Fang La. In the battle, Song Jiang and the others defeated Fang La's men and finally occupied Fang La's capital. However, due to the internal power struggle in Liangshan Lake, Song Jiang and the others failed to complete the plan of appeasement and were defeated by the imperial court's army. This time, it mainly showed the growth process of the Liangshan Lake Righteous Gathering and the power struggle within the Liangshan Lake. At the same time, it also showed the heroic deeds of the heroes of the Liangshan Lake and their tenacity and indomitable spirit in the face of difficulties.