A large vertical cave has a constant, strong wind blowing out of it from the bowels of the earth. If one was to jump into the currents they would have a controlled ascent on the winds till they reached a height where their weight and the winds force reached equilibrium. Impossible to climb down naturally. What is it? Natural winds from the earth or a complex magical protection for an underground lair?
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.
A great treasure has been stolen from the Palace and taken to the nearby Temple to the Bitch-Goddess Atrath Klee. The King demands that the party go and retrieve it - the only snag is that the Temple is guarded by potent magic that will kill any male who steps inside. It's just as well that the King has a stash of Girdles of Gender Alteration for just this circumstance.