Who is behind the death of the five families?

Shi Tian's Dragon Hunting Tactics: The Prince of Yan is behind the scenes.

Pi Jianqing was abandoned by his parents since he was born, because on the first day of the New Year's Day, the prince came to visit, and his parents were afraid that he was unknown and didn't want to keep him at home again. Only grandma doesn't want to give up like this. Shi Tian's strategy to find the dragon is five. Everyone's Yan is a bad person. To this end, in order to get out of the mountain again, I chose the daughters of five wealthy families to sign marriage papers with Pi Jianqing and left his life. Although his illness continued, he still grew up safely to be nine years old. At the age of nine, she was taken to Wanshou Palace, the most famous Taoist shrine in Xijiang by her grandmother. In front of the statue of the holy Lord Xu Xun, grandma solemnly announced to Pi Jianqing that from now on, she would teach him everything she had learned in her life.