It seemed like the Treasure Palace appeared three days ago, found by the Human roaming in this area.
She was barely able to save her life as by the time she had found it, there already been around Grimm Monsters gathered around it.
Fifteen of them had chased her; they had chased for nearly a day, till she reached close to the city; when she entered the city, she was quite bloodied, barely hanging to her life.
Still, because of her, we were able to secure this site before it was too late.
Sometimes when the treasure palaces appeared, and one side secures them so tightly that the other side did not even know they had appeared.
Sometimes even if they know, they don't go for it as the price of going after is greater than they are willing to bear, but most of the time, both sides share as the price of not sharing is too great.
We humans barely let have the Grimm Monsters any advantage. Even if it cost us arms and legs, we still go for it.