It is said that Yang Jian and Monk Hanshan were engaged in magic combat, choosing the method of meditative confrontation, but Hanshan forgot to mention the rule about not seeking external assistance, which led him to be besieged by the Howling Celestial Dog and the Silver-eyed Golden-winged Eagle from above and below. Now trapped in a difficult fight, he could rely only on the Great Buddha with Golden Body to repel the Howling Celestial Dog and Silver-eyed Golden-winged Eagle time and again.
Leizhenzi saw that Hanshan had not yet been struck down and felt that he was losing face. He was Yang Jian's fellow disciple, with their master being one of the Twelve Celestial Chiefs, and he was there on orders from the Heavenly Venerable of the Thunder Department to lay down thunder, and just happened to be spotted by Yang Jian, who asked for his help.