This book is wonderful! Formatting is excellent, content is excellent...I'd have to say the best part, is that there are little blurbs with each creature, outlining a possible scenario with one, in case you're somewhere, and you get stuck, or you're just looking for a new challenge for your players. There are creatures from the original game, and original content: the former come from all sorts of sources, and includes Arch-Devils and Demon Lords; the latter includes variations on "core" creatures, such as demons, devils, ghouls, oozes, orcs, and -so- many more besides! There are also a handful of playable creatures, which is a very nice option for groups.
The only "problem" I encountered, was a minor hiccup with getting the .PDF, but that was dingbattery on my part. And you know what, that made me all the more excited when I opened this for the first time.
This book is worth every single Copper, or even Electrum, or piece of real-world currency you put into buying it. Truly a beautiful work, and every retro gamer ought to have a copy!
[5 of 5 Stars!]