“ 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.”
“ It is dreadfully rude to carry a fishknife whilst talking to a Merman or Mermaid, as they think of them as we would think of thumbscrews or other torture devices.”
“ Anything not bolted down has a chance of moving about when unobserved. The items are smart enough to open simple latches, or break weak bindings. The rate of this oddness seems to follow certain astrological patterns.”