I’ve seen a hand‑written note tucked into an old burial chamber that mentions a “fury of iron” built by a tribe that specialized in hollowing out the heart of a single large stone block. They would carve a tiny chamber inside, fill it with hot charcoal and metal shavings, then seal it with a wooden lid. When the metal oxidized, pressure built until the lid blew off, sending a stone ball the size of a small house straight out into the courtyard. It wasn’t a city‑level destruction device, but if a town had already abandoned the area after a storm or war, the whole place could look like it blew to dust. I suspect the tale got exaggerated over centuries; the mechanics were simple but effective enough to frighten even the most stoic neighbors.