(3) Base Camp
The hardest word in the book is in the epigraph, and you can blame Ralph Waldo Emerson for using "guerdon" when reward would suffice. (Put down the thesaurus and go for a walk, man.)
Aside from that, we occasionally run into the author-created terms for supernatural characters in the novel, like coerlfolc and syndrigast and ymbrynes. Don't worry, we have no idea how to pronounce these words, either, but it doesn't affect the enjoyment of this fast-paced novel.