Vita Nostra because it has an interesting magic system. Piranesi because it also has a weird magic system. I didn't read it this past year, but the first one that came to mind was Tigana. That book was rather weird for me, because the process of reading it wasn't very enjoyable, but after finishing I loved it. If anyone has suggestions for fantasy or sci-fi books with weird or non-standard magic systems I'd love to hear em. I've already read most of the big names like Sanderson.
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