Before going up to the stronghold, Sun Li volunteers to infiltrate the Zhu Family Manor, which Liangshan has failed to take in two offensives.
As Sun Li has learnt combat from the same teacher as Luan Tingyu, the martial arts instructor of the village, he wins the confidence of the Zhus.
Sun Xin and his wife are put in charge of an inn which acts as a lookout of Liangshan after 108 Stars of Destiny came together in what is called the Grand Assembly.
The couple participate in the campaigns against the Liao invaders and rebel forces in Song territory following amnesty from Emperor Huizong for Liangshan.
Although conferred the title Martial Gentleman of Grace (武奕郎), he does not want to serve the government and returns to Dengzhou with his wife and his brother, where he lives as a commoner.