悪樓
あくる

Translation: evil watchtower
Alternate names: Anato no akujin (the evil god of Anato)
Habitat: the Seto Inland Sea
Diet: omnivorous; including boats

Appearance: Akuru is a monstrous fish found in Japan’s oldest mythological texts. It is described as both a giant fish and an evil god. It lived in the Seto Insland Sea off of present day Okayama Prefecture. It was so large that it could swallow a ship in a single gulp. It was slain by the legendary warrior prince Yamato Takeru, son of Keikō Tennō, the twelfth emperor of Japan.

Origin: The origin and the meaning of akuru’s name are mysterious. The giant fish appears in Japan’s earliest mythical chronicles such as the Kojiki and Nihon shoki. Its story appears in the local folklore of the Seto Inland Sea, however the name akuru doesn’t appear to have been used until the 20th century. The ancient texts describe Yamato Takeru’s subjugation of various tribes during the period when the Yamato court was trying to seize control of Japan’s land and sea routes. In the areas around Kibi and Naniwa (present day Okayama and Ōsaka), Yamato Takeru exterminated various evil spirits who were disturbing the peace and challenging the central government’s control. He is said to have conquered many mountain and river gods–including the god of Anato, who is believed to be the akuru.

It has been suggested that the “gods” that Yamato Takeru conquered–including akuru–were actually bandits (“mountain gods”), pirates (“river gods”), and other groups subjugated by the prince on his campaign. They may be examples of people who were transformed into yōkai by chroniclers for symbolic effect, like tsuchigumo–a tribe of humans who were turned into yōkai by storytellers. The giant fish-god of Anato may have been a mythical representation of a leader of a group of pirates or rebels whom Yamato Takeru exterminated as a favor to the governor of Kibi.

Legends: Yamato Takeru was sent on a long journey by his father to subjugate the the Kumaso people–a mythical ancient people who resided in south Kyūshū. After conquering the Kumaso, he sailed back to Yamato via the Seto Inland Sea. While traversing a shallow section of the Seto Insland Sea known as Kibi no Anaumi, his ship was attacked by a giant, evil fish. Before it could swallow him whole, Yamato Takeru leapt off of his ship and onto the monster. He clung to its back as it thrashed about, and he slashed it over and over with his sword until he killed it.