VII. The Steerswoman by Rosemary Kirstein
Randall "XKCD" Munroe pitched me on this over dinner: "All these different people kept recommending them to me, and they kept telling me that I would love them, but they wouldn't tell me what they were about because there's this huge riddle in them that's super fun to figure out for yourself. "The books were published in the eighties by Del Rey, and the cover of the first one had a huge spoiler on it.
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