Eighteen evil spirits in Luohan Town made a number.

The number of evil spirits in Luohan Town is six. Eighteen arhats refer to sixteen gods appointed by Sakyamuni Buddha, among which sixteen arhats are very common in Buddhism and are usually used to ward off evil spirits. And "6" is homophonic with "Shun" in Chinese, so the eighteen arhats are considered to ward off evil spirits, so the number "6" is used.