This is an acorn of mass destruction. It’s stored in a small box with room for six but only containing the one.
A strange, mystical box, with many rumours attached, that does not want to reveal its secret…
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?