The initial symptoms are easily confused for rabies. The infected eventually lose the ability to speak normally, their words relegated momentarily to growls akin to a wolf. However, they also gain increased senses, also akin to a wolf, as if a form of sexually-transmitted lycanthropy.
The disease causes deformation of the frontal lobe and swelling of the adrenal and pituitary glands, increasing anger, hunger, and impulsivity. When the infected is excited or enraged, they bled from their eyes, nose, fingernails, and gums, thereby spreading the disease to those they hurt. The longer the infection, the more extreme the change, to the point of appearing akin to werewolves.
What is known is that the disease originated from a wolf with a wasting disease, possibly in the 7th Century. When the Norse ate the heart and brain of this animal during a winter solstice in a ritual to survive the long winter ahead, they were infected, the disease mutating in a human host. The infected Norse became some of the most feared warriors in history, alternately known as "Berserkers" or, in the modern context, "wargs."
In the 21st Century, a group of people in the wildnerness were bitten by a wolf infected with Lukos, prompting a spread of wargs across Washington before it could be contained. Wargs thereby spread to Seattle, where Team Arrow had to deal with them, though Green Arrow was infected temporarily in the process of his first fight with one of the wargs.
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