Ghosts are not scary, but wrong but inviolable rules are scary.
Nine hundred years ago, the former chief of Beiyin was sentenced to ten reincarnations by a ruling that he could not appeal; nine hundred years later, when a group of living people brought the memory of the same deceased to the Zangzhi Teng Pavilion, he brought the orphans of the dragon clan and a group of people whose origins had been erased by the righteous way. Companion, from the "purified" unjust cases, he found out the truth that the Pure Karma Tribunal built towers with dragon bones, raised false Buddhas with the power of wishes, and maintained order with dead souls. Since the rules did not allow the case to be overturned, he led all the ghosts to kowtow to the sky and made the rules the defendant.
Concept: Ghosts are not scary, but wrong but inviolable rules are scary.