Easy to read layout and beautiful, evocative art.
Some of the options for flavouring up the ratfolks easily swing between terrifying and hysterical, at times both, not only giving ample room for encounter variety depending on the desired moods, but also a nice anticipatory laugh. Would you rather the ratfolk assaulting you appear from the shadows with a butcher's cleaver, a fanciful feathered hat or a small pet rat on its shoulder?
Make no mistake however this is the creepier, dangerous type of ratfolk, and ones that'd make for involved antagonists, either through force or their network of whispered information.
The monograph, while easy to read, explores in detail the ratfolk variants and hierarchies that govern their underground nests, providing subtle world building throughout.
It provides as well a comprehensive list of potential conflicts and encounters, and a sample of a ratfolk nest - with a map of its layout marking out the potential traps, encounters, and goodies that may wait inside.
Absolutely worth its price!