From publisher blurb: Use malevolent outsiders in your worldbuilding, character development, and storytelling! History and mythology present us with many devils: Satan, Lucifer, Beelzebub, and Mephistopheles, for example. While modern religion often presents them as aspects of a singular, ultimate evil, they were originally separate and unique beings. Demons likewise have many real-world counterparts, sharing a number of qualities. All of these beings are powerful, destructive, and originate in some sort of underworld. Legacy roleplaying games lump these evil entities from other planes of existence together under the category of fiends. Devils have their own rules and hierarchies, while demons are essentially destructive anarchists. It’s not a requirement that fiends be part of your fantasy worldbuilding. Many people skip over them based on their personal beliefs, because it takes the fantasy uncomfortably close to subjects they don’t feel are appropriate for a game. You’re free to agree or disagree, but in many ways fiends can be a trope as essential as spellcasting. They can open up conversations about virtue, the nature of evil, and what it means to be a hero. The existence of demons and devils, to be impactful in your setting, should connect to cultural beliefs about reality, cosmology, and even the nature of good and evil. Beyond being a hardcore opponent to overcome in combat, the existence of fiends should serve to validate assumptions about everything, from the facts of the setting’s history to the nature of magic itself. In this book, we’ll show you how to utilize these malicious outsiders in your worldbuilding endeavors. You’ll see how they can influence character, setting, and story elements. By the end, you’ll understand how to make fiends into an essential, useful, and entertaining part of your campaign.