Over 1,000 years ago while serving the emperor of the Qin Dynasty, Xu Fu sailed to an island to conduct research on achieving immortality. Using Taoism as the foundation to his research, Xu Fa experimented with the Tao of organisms by fusing them together and created fabricated creatures as a result.
The butterflies of Kotaku have human faces and stingers to infect their victims with Arborification. They can also release powder from their scales, causing whoever inhales it to feel lightheaded.
The centipedes of Kotaku have human faces and are much larger than ordinary centipedes.
The Watatsumi (海神 Watatsumi?, Viz: Kaishin Sea-Gods) are large under sea monsters that prevents anything from leaving Kotaku if it has not come from Hōrai's floodgates. They have snake-like bodies, tentacles with deformed faces and sharp claws, and have the head of a human.
- Further information: Sōshin
The Sōshin (竈神 Sōshin?) are incomplete, lower-class monsters and serve as guardians in Eishū by killing any humans that trespass on the island. They have low intellect but are capable of speech on rare occasions. They live in a nest deep within the valley of Hōjō and are forbidden from stepping foot up in Hōrai.
- Further information: Mōnshin
The Mōnshin (門神 Mōnshin?) are another type of lower-class monster guardians but are much more stronger than the Sōshin.
- Further information: Dōshi
The Dōshi (道士 Dōshi?) are monsters of a higher-class. Unlike the Sōshin and Mōnshin, the Dōshi possess intelligence and are much stronger. They reside in Hōrai where they undergo training in the ways of Tao as students and servants of Lord Tensen.
- Further information: Tensen
Tensens (天仙 Tensen?, Literally meaning: Heavenly Hermits) are synthetic humans created from Human and Plant Tao. They are the supreme beings of Kotaku and rule over all the monsters. The Tao of each Tensen are greatly refined and goes beyond human limitations, being comparable to that of the gods. They benefit from an elixir known as Tan where their lifespans are extended with large amounts of Tao robbed from humans. They are also able to regenerate their bodies from any form of injuries they receive in an instant and are able to unleash a transformation known as their Kishikai's.
After fusing with Zhu Jin, the Banko created gigantic monsters resembling Buddha but with flowers as faces. The bodies of the monsters are made from vegetation and are either male or female. If come into contact with anything living, the monsters will cause the victim's body to be engulfed in flowers and die.