When a wizard named Mendalus develops a spell that summons an obedient woman named Catherine--exactly like any other summoning spell--it creates chaos in the wizard-metropolis of Meltheria, as many interested parties struggle to understand the nature (and legality) of the Catherine spell, while vast fortunes hang in the balance.
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.