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.
The bronze Gladius Tyrvaard carries has been enchanted by the Spirits to be very heavy to any but the wielder. Tryvaard (or any others who use the blade) will find the sword light and easy to wield. Those on the receiving end receive a strike as if made by a much larger and heavier blade. For such purposes (damage, ease of parry, breaching armor), it strikes as if it were a two-handed sword of great size. The blade, being spirit-forged, is also extremely durable, well stronger then normal bronze.