Why were there so many monsters in Song Dynasty?

Since the Eastern Han Dynasty, Buddhism has spread to the East, and its influence has deepened day by day, providing a suitable cultural atmosphere for the rise of "mystery novels". Most of the writers who create "strange novels" are not Confucianism, Buddhism and Taoism, but use people and ghosts to express their feelings about the real society in different ways. China has a tradition of believing in witchcraft since ancient times. The Qin and Han Dynasties respected immortals, while the late Han Dynasty worshipped ghosts. This is the social basis for the rise of "mystery novels".