Hyakki-Yakou (百鬼夜行; "Night Parade of One Hundred Demons") is a term used in the series.
Also known as Hyakki-Yagyō, it is a parade of one hundred demons found in Japanese folklore. Said to take place in summer nights, anyone not protected when coming across one will be killed. The children’s game Hyakumonogatari Kaidankai was based on this idea. Hyakki-Yakou's have been popular in visual art in Japan.
- Devil Summoner: Raidou Kuzunoha vs. The Soulless Army
- Devil Summoner: Raidou Kuzunoha vs. King Abaddon
Raidou Kuzunoha vs. The Soulless ArmyEdit
Three Hyakki-Yakou's must be fought at different moon phases to collect items needed before fighting the ultimate boss Beelzebub.
Raidou Kuzunoha vs. King AbaddonEdit
A Hyakki-Yakou will be fought in the case file Guard Mission: where Raidou must go to Kasumidai to defeat it before any VIP's or soldiers are hurt. It is made of Pretas, Enkus, Nekomatas, Okiku-Mushis, and two Gashadokuro.