I made refs for all the yudaes! :D

Xyan, Praxus, Akhet, and Aiko, the main four.

The satanic a-holes plus Kaen

Not me actually doing research to give Angel a semi-accurate outfit for someone who died in the 80s-

Ailanii and the humans, Hela, Richard, and Soren. Soren really doesn't have much of a role canonically but he deserves a spot here :)

[DATA EXPUNGED], who I'll just call the Author, and Squiggle.

And of course the sillies that are not really important but exist.

Now the fun part: I'm officially opening the yudae species!

I know some of you already have yudae OCs, and that's perfectly fine, this is only here for those who wish to make one or for accuracy.

"Yudae" is derived from the Japanese word "Yurei." The yurei are a type of yōkai. Imagine your typical pale ghost with long black hair, and you basically have a yurei.

Yudae, of course, are much different than this. Yudae are humanoid spirits with wings (usually looking like that of a demon) and tails (always spaded in some way). They exist in a variety of colors, usually representing something about them or their death in some way (e.g. Gradient was white to represent innocence before he turned, Sasha is yellow to represent the betrayal that led to her death). Yudae have no memory of themselves before death - maybe a few snippets and the last few seconds before death, but usually their names are not known to them, and they usually make one up for themselves. They tend to look similar to what they looked like when they died, in a sense that they retain their human features and whatever outfit they were wearing. The only addition would be the wound/cause of their death, which would appear black.

Some examples of these injuries, to show what I mean, would be the area on Praxus's head where his skull had broken during his death, and how Aiko's hands fade to black at the end (her death was electrocution, by sticking a fork in an outlet, so that was what was most effected. On her chest and arms her veins would be black leading up to her heart). If that yudae had previous injuries before death, those would appear too (like the scars on Akhet's arms and the scratch over Gradient's eye).

The yudae, as I've mentioned, appear in some color of either the creator's choice or as a representation of them or their death. Their "aura" (outline) would appear as a bright hue of this color, and the rest of them would be varying other shades of the color. There is no true white unless that is their actual color, like Gradient was at first. If there is white, it's a very light version of their color.

With their wings, yudae can fly. They can also levitate without using them. However, levitation only works to a height of about three feet, and flight does not allow them to leave the Earth's atmosphere, leaving them stuck in the limbodeic plain on Earth.

There's two (known) types of yudae: limbodeic and hellbound.

Limbodeic yudae are yudae that reside in limbo. They bear the classic look of a typical yudae, with monochromatic hues like I just described, and wings and a tail. Their blood and any wounds they receive are black, and any wounds they receive in the afterlife will appear with black blood.

Hellbound yudae are yudae sent to hell after being in limbo for any extended period of time after awakening (these are NOT spirits sent to hell by default after death. They go to limbo FIRST, and would've been killed in limbo to go to hell). These yudae look a bit different: their skin is black, often fading to their original color at the tips of their fingers, tail, hair, and/or wings. Clothing colors tend to stay the same, just appear darker. Their eyes go from pale to black, having black scleras, but the pupils remain the same. Their blood does not appear as black, but crimson, similar to human blood.

Note that not all killed limbodeic go to hell. If they are of worthiness, they can still go to heaven, but there is no solid "heavenbound" design for yudaes as of right now.

Of course, some yudae can enter limbo as ritualistic. Ritualistic yudae are yudae "turned" by a certain ritual following their death. The ritual twists their morals and judgement, turning them into what could be described as "crazed, animalistic psychos."

At first, ritualistics have no difference from normal yudae. The only truly noticeable difference is the fact that they commonly have nightmares and visions depicting violent, crazed versions of themselves convincing them to "let go." These visions will continue until the first full moon after their death. This is when they actually "turn." Any lighter gradients (haha, get it?) on their wings and hair will turn black, as well as their fingertips and usually the tips of their tails, and their scleras will turn black. However, the left eye of the yudae will immediately "combust," I guess is the word for it, leaving a bloody hole in the yudae's face where it used to be. This hole is filled with the watching eyes of any soul that yudae consumes. This hole is covered by an almost animated red scribble, which can fade away if the yudae is actively healing themself.

Consumption, the power they gain, is the ability to take a soul from a spirit's body and meld it with their own matter. The soul's consciousness will enter a "void," while the physical being will be absorbed by the ritualistic. This is like a drug to the ritualistic, which is where the twisted morals part comes in. The ritual twists their mind into believing this is a good thing, and the addictive nature of consumption often dooms the yudae to lose their mind, forever craving for more no matter how much they attempt to satisfy their hunger and bloodlust.

Currently there is no way to save a ritualistic yudae, only capture it where it cannot hurt anyone or send it to hell (even if they are good in life, ritualistics lose the ability to enter heaven due to their violent nature that cannot be changed).

Yudae can be "killed" a second time by a certain object, or "spirit totem." This totem is usually something that they owned in life that was special to them, or, in the case of most ritualistics, the weapon that killed them (assuming they were murdered, which is how most who become a yudae happen to die). Once yudae are killed, they "pass on" and either enter heaven or hell, depending on how they were in both life and limbodeic afterlife.

As I've mentioned, every yudae has a soul. This soul resides inside of their heart (which, unless they've been stabbed, is still actually there). It appears as an orb of their color with flames emitting from it. There is one eye on it, which represents their consciousness. If their soul is removed from their body (a very painful experience, may I mention), their conscious being will remain inside their soul, and their body will be left a lifeless husk with no ability to move or do anything. This husk will fade without the returning of their soul.

While hellish spirits aren't yudae, I'll include them here too:

Hellish spirits (like Sasha and Barley) are spirits that went to hell by default. Usually these people are between the lines of criminals and people who just didn't really have the goodness in them to go to heaven. These spirits will appear very similarly to their living selves, just usually tinted a specific color (like how Sasha is kinda tinted yellow, and Barley's kind of blue). Sometimes they have tails, and very rarely they have wings. It depends on how much they remember about their life. Hellish spirits remember more about themselves than yudae, but not everything. Usually they remember their name, like Sasha, but some, like Barley, make up their own, either because they don't know their original name or wish to change it for personal or external reasons.

I believe that is all. I'm willing to answer any questions you may have, and have fun with this :)