User notes: Lexicon of the Arcane is the magic rule book for the Circe roleplaying game. This book covers the physics of magic, spellcasting, spell countering, divination, the effects magic can have, design of magic spells and items, and the magical traditions of the Circe setting. The majority of this book is finished and usable, but some of the book's chapters are notably incomplete as of Release 1.3, with headings lacking text or "chapters" that have only a single paragraph.