Fury

Fury (sometimes called rage or frenzy) is an intense, uncontrolled anger in response to a perceived egregious injury or injustice. Fury is considered one step higher than the anger many people experience, in that it is all-consuming and both destructive and self-destructive.

An individual "in Fury" will experience profound physiological and psychological effects, such as increased heart rate, elevated blood pressure, increased levels of adrenaline and noradrenaline, insensitivity to pain, heightened strength and speed and faster reaction times. When an individual makes the conscious decision to go into Fury, it becomes the predominant feeling behaviourally, cognitively and psychologically. In extreme cases, the individual may exhibit visible differences, such as eye colour.

In humans, Fury at this scale is relatively rare, and the ability to control or weaponize it even more limited. Fury's counterpart is Serenity

Description
Due to it's limited occurrence, little is known about Fury. However, physicians and researchers at the White Wolves believe it is a psychological phenomenon triggered by overwhelming rage, and worsened by past trauma.

Individuals who can use Fury to their advantage must still be very careful. As Fury requires the user to sit on the edge on chaos, those who are untrained or not strong enough, some will be mentally broken.

Because Fury is the foremost, consuming thought, it will overshadow other thought processes and cause the user to lose inhibitions, act more explosively and can endanger those around them, including friendlies. Many people who attempt to use Fury fail as the thoughts and trauma engulf and defeat them.

Jack Fox
Jack isn't the first person to use emotions on the battlefield, though he is the first known person to use Fury. He can trigger his Fury manually, typically through memories of witnessing his parents' deaths, his time in the British armed forces, the 1997 Motherbase Attack, Serena's capture and the attacks on the United Nations and his cousin.

When in Fury, the frenzy emotion is at the forefront, making him a creature of sheer will. This means that Jack gains some level of pain insensitivity, increased speed and strength, allowing him to move faster and pull more weight, and his reactions are sharpened.

During this time, Jack is even more relentless, few enemies living to tell the tale of the man possessed. His Fury has been described by some as "weaponised PTSD".

Anna Fox
Anna was taught how to master Fury by her father, and Serenity by her mother. Unlike her parents, Anna can harness the power of both Fury and Serenity simultaneously.

While fighting Nina for the final time, Anna entered her own Fury, however, she began to see Jack's past too. Events decades before her own birth were crystal clear in her mind and empowered her Fury even further. This is one of several instances of Jack and Anna's supposed Spirit Link

Anna Fox (THP)
Anna Fox was trained by her father, Jack, in the "art of Fury". Once she was 18, she entered training, where she learnt how to employ negative memories to serve her, her Fury powers increased over times as she had more experiences she could use. Like her father before her, Anna's eyes will transition from the natural purple to a blood red when she is in Fury, a sudden change that scared Lilith when she first saw it. She will also lose her inhibitions, massacring enemies left and right just for existing, and in rare cases, she may lash out at friendlies.

Through her life, Anna has experienced many hardships - such as the loss of her parents and hundreds of attempts on her life, and attacks on her home, the Elven Realm - these experiences help her to channel her emotions, into Fury. Due to her relentless killings while in Fury, Anna's name is known throughout the Realms of her home universe, and her presence strikes fear into the Dark Forces.