From Introduction:
White Robes, Black Hearts: Enigma of the Arcanexus is a challenging campaign adventure for characters levels 3-5, and serves as a logical continuation from the previously released free module Dead Fire. It is recommended that the PCs consists of 4-6 characters (about party level 5), and it is almost vital to the adventure for a party to include a wizard or sorcerer, and a rogue. Certain areas of this adventure are extremely dangerous, and so you should decide whether you wish to keep extra NPCs on file for the players to adopt, or whether you want to be liberal in your interpretation of the rules for lingering at death’s door and the rules regarding the limitations of resurrection. While this adventure is designed to be difficult, it is not designed to kill parties.