Water-breathing people whose anatomy — gills, distinct lungs — turns out to be Louis's salvation.
Naiad biology is the technical problem and the answer of this chapter. When Carl dumps Princess Lunette's body on a cot he realizes she has gills and is a full naiad, not a half-blood, and worries that means she is water-only. Mordecai confirms it.
Edgar turns the problem into the plan: naiad lungs are shaped differently from human lungs and must be cut carefully, but with the Kua-tin Rebreather grafted into the bronchial and a Water Breathing Scroll to grow gills, Louis can live on them. Lunette had originally been orphaned as a half-naiad after her own mother was killed at the hands of high elves.
The water-breathing people whose organs replace Louis's machine heart and lungs.
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