Pro tip: If you have a modern Kindle (2022+), use EPUB via Amazon’s “Send to Kindle” feature. If you have an older Kindle, use MOBI.
In an era dominated by discussions of bio-hacking, nootropics (real drugs like Modafinil), and the "grind" culture of Silicon Valley, The Dark Fields is more relevant now than when it was written. The Dark Fields by Alan Glynn aka Limitless EPUB.LIT. MOBI
The EPUB format is the most widely supported ebook format, compatible with Apple Books, Google Play Books, Kobo, and most third-party reading apps (excluding the Kindle ecosystem directly, though Calibre can convert it). Pro tip: If you have a modern Kindle