The blue fury

A strange condition that spreads through contact infection that causes its suffer's to slowly descend into a mindless rage before death. Originally called blue vein its name changed after the biggest outbreak in history. The specifics also differ from case to case though all seem to follow similar paths, the loss of mental faculties and an increase in physical prowess until death.

Outbreaks

While It isn't clear where this disease comes from exactly, a connection has been made between outbreaks and the Sardian Ruins. The first recorded outbreaks took place in the Phervian empire as on several occasions slave groups were infected. In one situation an Phervian itself was infected and gorged itself on an entire slave camp before succumbing to death.
After the fall of the Phervians outbreaks happen few and far between but normally start out at sea, engulfing the ship unless it hits land or is boarded by another ship, these outbreaks never last long and only happen every few hundred years. During the blood age, a Dragon was infected, causing the largest outbreak in history, especially amongst the Shifter tribes, who named the disease Blue fury for the first time. Only a handful of outbreaks have happened since, with ships quarantined if discovered.
The Shrieker hordes, though showing no physical symptoms, other than their claws but that could be from the procedure to make them, were thought to possibly suffer from a variant of the condition.

Transmission and symptoms

To get the virus, you need to get the fluid, aka blood or saliva, into your blood. This doesn't seem to guarantee transmission as hardier folks seem to not be affected. At first, nothing seems to happen, some do get headaches or slight changes in personality. After a few days, veins around the wound turn ice blue and spreads out over the next few days. during this period the sufferer turns more aggressive and physical, while seemingly losing some of their mental faculties.
After a week the ice veins have spread throughout the body and the condition becomes incurable with nothing short of universal intervention. The fingernails also turn to bloody claws and teeth become sharpened. Shifters and Ware-people at this stage can't change to their Human form.
At some point, sometimes as the veins spread, sometimes after, the creature loses control and starts attacking mindlessly, though this can happen only for them to regain control later, it becomes harder and harder. This seems to always happen during periods of high stress, such as a fight and they no longer can tell friends from foes. A druid who suffered from the disease was said to never fall into this part, despite having the veins spread everywhere for a month.
Within two months at maximum, the sufferer dies, if not killed in fighting. some die before the veins even take full hold and some animals seem to die instantly.

Cure

If caught early enough, Clerics, paladins, and other magical healers can cure the disease, however, once the veins reach the brain, nothing short of world-changing magic can cure it.

Type

Supernatural

Origin

Engineered

Cycle

Chronic, Acquired

Rarity

Rare