Yōkai

The **Yōkai** are a species of multiple diverse supernatural creatures that live deep underneath New York, known as The Hidden City.

These versions of the Yōkai have a more specifically mutant origin than the yōkai of Japanese myth, having lived in a society that has evolved in a vast underground chamber now called the Hidden City. Because of this, the Yōkai comprise a people and culture that sets them apart from other mutants in the series who mostly only recently mutated because of the intervention of Baron Draxum, a Yōkai alchemist.

## Biology and Appearance

The Yōkai are extremely diverse in appearance and presumably biology. They commonly resemble anthropomorphic animals that vary in appearance from recognizable real-life species to unidentifiable fictional species with some Yōkai being specific legendary creatures such as jorōgumo, ogres, and mermaids. Yōkai can have bodies made of a sole material such as bone and can even look indistinguishable from humans as seen in Don Suave, though this phenotype appears to be rare.

Yōkai can be sapient or non-sapient. Sapient Yōkai commonly possess an erect posture (though not always), while non-sapient Yōkai can't speak and are seemingly used by sapient Yōkai as humans use non-human animals (as food, transport, etc.).

Compared to humans, Yōkai possess a longer lifespan and age at a decelerated rate. It may be possible that a 200 or 300-year-old Yōkai would be equivalent to a human in their 20s or 30s according to *Rise of the TMNT* writer Russ Carney.

## History

The Yōkai have existed for centuries and were originally mutated by a substance called Empyrean which spilt out of the Crying Titan, the most sacred place in the Hidden City. It wasn't until the series finale, "Rise", that the source of Empyrean was explained: Within the Crying Titan lay the long-dead skeletal remains of a Krang with a stash of ooze.

The Yōkai historically inhabited the Earth's surface as humans do currently, but at some point were driven underground by humans.

## Society and Culture

The Yōkai live in secrecy from human society, the majority of which reside in the Hidden City, though some live on the surface. However, Yōkai who travel to the surface must be cloaked in some manner (often via cloaking brooches) to protect their Yōkai identity from the human public and, by extension, the existence of the Hidden City. Some Yokai have the natural ability to shapeshift into human forms. The exception being safe locations Run of the Mill Pizza and the Grand Nexus Hotel.

Despite their shared origin with mutants in this continuity, Yōkai don't identify as mutants and the concept of mutation and "mutant" label is foreign to most as expressed in "Bug Busters" and "Sidekick Ahoy!". While they are decidedly distinct from mutants, most Yōkai (and mutants) can't distinguish a mutant from a Yōkai from appearance alone and simply assume that they are fellow Yōkai.

Mystic Powers are an established part of Yōkai society and are widely used to operate the Hidden City. Some Yōkai communities such as Witch Town are centered around the use of mystic powers. Yōkai seem to have their own writing system as seen on the Witch Town gates in "Donnie vs. Witch Town" and on alphabet blocks in "Hidden City's Most Wanted" with numbers that resemble the symbols of the Western zodiac, visible in the Grand Nexus Hotel elevators ("Bug Busters", "The Ancient Art of Ninja Hide and Seek", "Battle Nexus: New York").

Yōkai generally don't seem to regard traveling to the surface as taboo and despite being forced from the surface by humans, they don't seem to have widely held contempt or fear towards them as April O'Neil candidly traverses the Hidden City unchallenged by its Yōkai residents. Alchemy and science are seemingly outside of what is culturally acceptable as shown in "End Game" when the Council of Heads call the practice of alchemy an offense against the nature of Yōkai and when the label of "scientist" is used in a deprecatory manner by Yōkai witches in "Donnie vs. Witch Town".

## Individuals

* Amphisbaena
* Bat Librarian
* Baron Draxum
* Beverly
* Big Mama
* Bruce
* Cortex
* Cuddles
* Dastardly Danny
* Don Suave
* Evil Emerald
* Evil Six
* Freki
* Fox bellhop
* Exploding Frankie
* Garm
* Gentry
* Gus
* Heather
* Heinous Green
* Hueso
* Huginn
* Hush-Bats
* Komodo Dragon Yōkai
* Loathsome Leonard
* Malicious Mickey
* Mayhem
* Mermaid Pirate
* Minotaur
* Mira
* Muninn
* Otter bellhop
* Operator
* Owl bellhop
* Piel
* Red Fox
* Sarge Goyle
* Sea Serpent Pirate
* Sprite
* Sunita
* Troll