The armored cavalry deployed by Huyan Zhuo could not be destroyed unless barbed lances were used. Tang Long presented a drawing of such a lance and lance could be made according to the drawing. However no one was able to use them. Tang Long suggested： "My cousin Xu Ning， an arms instructor in the capital， knows how to use barbed lances. The art has been handed down from generation to generation. We can bring him to the mountain." Everyone began to thing how to lure Xu Ning to the mountain. Tang Long had a plan： "Xu Ning has a suit of goose-feather armor hopped in metal. It is a matchless ancestral treasure. Xu Ning cherishes it like his life. He keeps it in a leather box that hangs from the central beam in his bedroom. If we can get hold of that armor， he'll have to come here whether he wants to or not." Then he whispered his stratagem to Song Jiang. Military councilor Wu Ying sent Shi Qian to attend to this matter. Shi Qian， whose body was light as a swallow， excelled at leaping onto roofs and vaulting over walls. Soon he arrive in the capital. Shi Qian inquired of Xu Ning's residence， studied the surrounding area and located where the metal-bound goose feather armor was placed. Finally， he learnt that Xu Ning would be on guard duty the next day at the fifth watch. At the fifth watch， Shi Qian stole into the kitchen when Xu Ning was having something to eat. As soon as Xu Ning had lift， Shi Qian went upstairs to Xu Ning's bedroom. Xu Ning's wife， who heard sounds coming from the beam， asked her maid what it was. Shi Qian promptly squeaked like a rat. Thinking that it was only rats fighting， Xu Ning's wife went to sleep. Seizing this opportunity， Shi Qian snatched the armor. Xu Ning returned home and heard that his metal-bound goose feather armor had been stolen. Guided by Tang Long， Xu Ning ran after Shi Qian and ended up at Liangshan Marsh. Convinced by the gathered leaders， Xu Ning joined the forces in the stronghold. Later Xu Ning destroyed Huyan Zhou's armored cavalry with his barbed lances.
呼延灼的连环甲马，必须用钩镰枪才能破。汤龙献出祖传的钩镰枪图样，可以照图打造，但无人会使用也是枉然。汤龙说："我表哥徐宁，现在京城做金枪班教师，他家祖传使用钩镰枪，专破连环甲马。我们可以请他上山。"如何能让他上山，大家开始想计策。汤龙又说："他家有一幅雁翎锁子甲，是传家之宝，徐宁非常珍惜它，总是吊在他卧室的梁上，如能盗来，我可用计引他上山。"于是把计策低声告诉宋江。军师吴用派时迁前去。时迁身轻如燕，专能飞檐走壁。时迁来到京城，现打听到徐宁的住地，又查看了周围的情况，观察了放甲的地方，得知徐宁早晨五更入班的消息。于是，五更天，在徐宁用饭时，时迁趁机迁入厨房，待徐宁走后，他又摸上楼。徐宁的妻子听到梁上有声音，急忙问丫头，时迁赶紧学鼠叫，大家以为老鼠打架，没有理睬。时迁借机把甲偷走。徐宁回到家中，见雁翎锁子甲被盗，在汤龙的指引下，一路追赶时迁来到梁山，在众首领的劝说下也入了伙，后来，徐宁的钩镰枪破了呼延灼的连环甲马。
