Age of Gray
Just a few hundred years ago, Urnketh was a world shrouded in war. Every nation fought for access to the mystical resource - Hues, elements which can let one shape the reality around themselves.
But then, the Witches showed up. These individuals possessed the ability to generate and manipulate Hues freely. As just their will can affect everything and everyone, a lot of them took over the kingdoms. Soon, the age of war stopped, no one daring to fight in fear of their terrifying powers.
At the same time, Witchhunters showed up. They were ones brave or stupid enough to kill the Witches. Unfortunately, killing a Witch only makes all of the Hues inside of her to implode and spread, creating monsters that plague all of the races.
And as time passes, seems like the age of Witches is also coming to its end.