Blood Mist

Blood Mist, one aspect that makes the life of Awakened Beings more difficult to adapt to human society is the risk of blood mist. A chemical disturbance in the brain caused by the lack of nourishment or triggered by an extreme trauma, causing awakened to go on a rampage. In this state, awakened are ruled by their instincts for self-preservation and eating, causing them to rampage mindlessly until they have eaten enough to satisfy their instincts and return their human minds. Blood mist usually begins with the world turning into a red-tinted, horror-filled version of reality, the red world, the boundary between the real world and the void. Here, the awakened's body goes into overdrive, and the awakened begins a near mindless rampage. Everything appears as dark shadows unique to each individual. Emotions run wild and temporary insanity ensues. Once enough food is eaten or the awakened is snapped out of blood mist, they awakened experiences suicidal tendencies depending on the state of mind. 
Blood mist begins as a result of extreme physical or emotional trauma, when the conscious mind must shut down and all that is left is the unconscious mind/instincts. This can occur from extreme physical pain, excessive hunger, or deep emotional trauma. Blood mist always occurs for an awakening in impure beings. This is because, at the moment of awakening, the yoki has fully devoured all human parts of its host body and needs more food. The immediacy of requiring more food sends the newly born awakened into blood mist until enough food is obtained to satisfy the being's hunger and return their conscious mind again. 
Blood mist is typically associated with awakened, although claymores can sometimes enter or put themselves into this state. The skill to willingly put oneself into blood mist is "Berserker blood". 
Blood mist is caused by the impurity of an awakened and its yoki, which causes the copied instincts of the yoki to be separate from the mind of the awakened, manifesting as uncontrollable emotional and instinctual rampage. Beings with high degrees of purity (purified drach, awakened that have undergone THUMA) can enter blood mist and maintain their sanity and self-control (since their minds are largely or completely combined with their yoki's will).
From Noble's notes:
"The world turns into a crimson red version with a landscape that's unique to their perception. Surrounded by pits of fire, in a frozen land of crystal or to live in what could only be described as a living nightmare, composed by the faces and screams of her victims.
Some turn into shrieking maniacs craving only for blood and flesh while becoming juggernauts. Others are just as serene and calm, like they been before awakening and losing the restriction to eat humans. But some become suicidal and simply surrender to whomever that survives long enough to let the state pass by.
The times people turns into unstoppable forces of nature, screaming for guts and relive their worst memories, are the times when Blood Mist is triggered by starvation. If the awakened feels great guilt or deep depression they become suicidal. The reason they eat such inhumanly quantities is because their bodies demands it and they try to use the hormones and the blissful feeling from them to numb the emotional pain. If they think there´s no life after it then it´s not strange how they might give up completely.
From those that experienced a relieved calm had only done so the first time they entered the blood mist state, at the moment of their Awakening. This is the determined factor for how the affected being will react. If the stomach is full or satisfied at the time then the newly created awakened won't enter frenzy. It would still see everyone as an enemy but act out of self defense, not hunger. And depending on how the Claymore was then it could very well act like it normally would while under the Blood Mist state.
When Yoki suppressants where digested before the moment of awakening, the newly awakened being acts with a undisturbed calm. A peaceful harmony plastered all over the face. The being was highly intoxicated from the suppressants and fully capable of rational thought and speech. But they can't turn back to human form."
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An awakened in blood mist from newly awakening, should it be deprived eating a human for too long, will forget its human form and possibly become permanently mindless.
Aggressive awakened in blood mist have their strength doubled and their hunger tripled, making them unstoppable juggernauts.
Blood mist wears off after a while, usually after food has been obtained.  Awakeneds generally have no memory of what they did while in blood mist.
Awakeneds which have many episodes of blood mist are generally killed quickly due to mindless rampages and are considered mentally ill.  Blood mist Sullivan is the only case known of permanent blood mist.  It is unknown if he still has this after Blanc's creation of a body for him although this is unlikely.  Another prominent case of blood mist mental disturbance is Angel who gets them at random intervals due to her extremely traumatic past.
An awakened in blood mist can be calmed and returned to normal much more effectively by those they care for and love.  In some cases, this is the only way to return a blood misting awakened to normal before they fully exhaust themselves into ending their own blood misting.
Fruits of Labor cause blood mist, making them unfit for consumption.Category:Terminology