Blood As Gold

A normal boar? For fuck's sake, you think it would take this many people to take down a fucking boar? It has gold blood! It won't stop until we cut its damned head off or get it right in the heart. They're all like this.

— Vissente Salucci

Around Lake Muror, and throughout Mount Erina, there is a pervasive curse. All the wildlife that reside in the area bear strange, glittering gold blood, rendering them unnaturally strong and difficult to kill, and very territorial. Among those who seek to protect humanity from their powers are those who aim to reverse engineer this curse and turn it into a gift for their soldiers.

Properties

The most obvious property is turning blood into a liquid gold-like substance, which has the immediate effect of making the skin a similar toughness to metal. Depending on the animal, it can also affect bones and similar parts of the body, turning things like horns and antlers into sharpened gold.
Many of the beasts with this condition are observed to be more violent than non-gold blooded counterparts, and fiercely territorial. They are very resilient, taking many strikes to fell and even surviving the loss of limbs that would be fatal otherwise. Some have claimed to see creatures with lost limbs grow new ones of solid gold, but no specimen has been captured with this trait.
While golden blood isn't contagious, coming into contact with it can be quite painful, resulting in burns and numbness. These properties fade in intensity the longer it has been since the blood was in its host, and eventually the blood will become inert and safe to manipulate in the way gold would typically be handled.

History

The valley around Lake Muror has been full of golden beasts for as long as memory holds, though the number of human ruins on the lake shore and beneath the waters suggest it was once far safer to live in, or that it was considered worth the risk.
For the last fifty years, the area has been considered 'contained' by the field squadrons of the Panacea Foundation, who patrol to prevent gold-blooded beasts from harming those who live nearby. In recent years these patrols have met with increased resistance, with the territory of these creatures expanding to push further from the lake and overrunning the human fort of Cuandune.
In response, the Panacea Foundation has increased its research into reverse-engineering the golden blood, with the hopes that their learning can be applied to their soldiers to make them more capable of fending off beasts, or to find a way to remove its benefits to make them easier to defeat.

Origin

No-one knows how this curse came to be. The best guess is that it has something to do with the properties of Lake Muror itself, but any effort to investigate is met with fearsome gold-blooded beasts at every turn.
A possibility for enquiry might be to look for the source of the river which feeds Lake Muror, high in the crumpled cliffs of Mount Erina. Unfortunately, the last squadron sent there has yet to return or report back, and are presumed lost.

No, we can't just "do a blood transfusion". Gold or not, wolf blood isn't really compatible with humans. Wrong blood type. To make that work you'd need to do so much to the blood that, I mean, it'd just end up being glittery plasma. It'd take so long it wouldn't work, I don't think. We'll have to try something else.

— Cearra Herriot, Research at the Panacea Foundation

Human Gold

Though this curse has been present in the area for hundreds of years, and despite the proof of human habitation in the area before and during this time, there is no evidence that a human has ever had golden blood.
Many attempts have been made by the Panacea Foundation to turn human blood to gold, with the results of these experiments being closely guarded secrets. Given the apparent toxicity of gold blood, it's likely that every attempt has resulted in the death of the test subject.