As a Ravenloft DM and the creator of the Mordenkainen's Magnificent Statblock , the release of this product delights me as nothing else. With every one of the 140+ spells you get a small note written by Mordenkainen which really brings the reader's mind closer to the genius of Mordenkainen and how he sees the world. The spells are quite balanced , creative and well-thought. There is some art too. what I appreciated the most is the lore. I don't want to spoil anything for but it really gives any DM reading it new depths regarding the vistani story. A lot of the magic items can be used in your generic CoS game while if you are running a homebrewed Raveloft campaign (Like i do) you are going to be amazed with almost everything found in the treasury of magic items.
TL;DR Just buy it. You will not regret it. It will expand your Ravenloft experience beyond what any words could describe.
[5 of 5 Stars!]