Uses iron to explain why traditional (aboveground) fortresses exist in a magic-rich world, how humans survive in the face of all the magical races, why fairy races fear iron, and why mages can't cast spells while wearing armor, using the "iron abjuration" spells create key, fortify, wall guard, conjure sour, grounding, iron awe, iron demense, tower of iron will, torus of disjunction, and mold iron abjuration.