From publisher blurb:
Welcome to Monstrous Personas, a new sourcebook for 5th Edition (5e) written by Miguel Colon of Legendary Games, newcomer Ayumi Morris, with additions from Kim Frandsen, Geoff Gander, and Beth Jones! The wonderful art is provided by the absolutely legendary Phil Stone!
In these pages, you will find uses for monsters that have either been long deceased or recently slain by your players! Spirits left behind by fallen monsters become available as resources for players and NPCs alike as templates to grant them new abilities! Within the pages of this book, we examine monsters, each with art crafted by Phil Stone, and see their effects when their spirits are absorbed, causing a transformation which allows others to utilize powers and abilities that the base creature had access to in life.