“ Mining in a certain area turns all exposed skin (maybe just parts that are actively disturbing the chemicals that cause the reaction) of the those doing the mining to a dark blue color. Will wear off taking as many years/days spent in the mine. ... meeting a party of blue-skinned humans armed with pick-axes etc. Strange disease? Demon offspring? Curse? If they meet only one ex-worker, they will very carefully listen to any stories he says, no matter if drunken or insane, or just makes up to get a beer.”
“ The desert is a curse from the Water God upon the wicked people who live in the South.
Said people offended the Water God in some way, and so the Water God placed water-trappers, bizarre, water-sucking beings, in the soil, and within years, the wilderness became a desert.
Thus, the desert folk shamans have special powers that allow them to find water-trappers so that they can be dug up and their water harvested.”