I picked it up on Wednesday night, but due to having to write an exam for my Neuro class and being absorbed in the new WHFRP books I picked up last weekend, I haven't had a lot of time to look at it. What I have seen so far looks very promising though. The grell are really fleshed out and made much more interesting, as are the aboleth. Beholders, despited being an iconic D&D monster never did much for me- they seem too out there. When I first got the book, I read the mind flayers section, hoping for some great new ideas, but if you've seen the Illithiad, there is nothing new here. In fact, I much prefer Hellhound's view of the mind flayers in Unseen Masters. The real gem of this book are the tsochar, or the wearers of flesh- a new type of insidious abberation, which seem much more alien and sinister than anything up until now. The new critters section is pretty darn good too. I'll need to read more, but so far I'm liking this a lot better than Libris Mortis or Draconomicon, and it'll get a lot more use in my game than either previous book.