Spymaster's Garden (System Neutral)

From publisher blurb: Too many times have our adventure been cut short as reliance on magic turns around to bite us. However, there are alternatives to magic that some clever herbalists have explored and brought to light. In this book, you'll be able to enjoy some of those options that may have previously only been the purview of wizards, clerics, and other magic users. This fourth book in the series tells of the dastardly tools a spy may use in their profession. In this book you'll find: 10 plants, where they may be obtained, how difficult it is to obtain them, and how to prepare them into something useful.