One day, Qin Qiong, Xu Maogong and others were talking in Juyi Hall when they suddenly heard a loud noise. At this time, the mountain patrol men quickly reported that a cave had collapsed under Baihuling in the back mountain. Xu Maogong, Qin Qiong and others rushed to the scene to check. The cave was dozens of feet wide and bottomless. Xu Maogong decided to send someone down to have a look, but no one dared to go down after asking several times. Finally, Cheng stepped forward.
Cheng bravely sat down, carried a bamboo basket along the rope to the bottom of the cave, found two boxes at the bottom of the cave, and Cheng took them out. In the small box is the big seal of jade carving, which is engraved with seal script; There is a big flag in the big box, embroidered with gold characters and a set of crown robe rails; The dragon crown is woven with gold thread, and the dragon robe is embroidered with gold thread.
Xu Maogong carefully looked at the eight seal characters engraved on the seal, namely "the devil on earth, the son of heaven with great virtue"; A line of characters embroidered on the banner is also "Devil in troubled times, son of heaven with great virtue". Everyone was surprised to see the crowned crawler again. Xu Maogong was glad that it was God's will, with flags, seals, robes and runways. It was God who asked them to set up a banner to destroy the Sui Dynasty in the name of the Lord. Finally, everyone unanimously elected Cheng, who got the seal and robe track in the crypt, as the emperor. Cheng refused, so he became the devil incarnate in Wagangzhai.