This is a great supplement that remains faithful to the Ravenloft setting of yore. In combination with the author's Children of the Night bestiary, it's made converting older Ravenloft adventures (from 2E and 3.x) much easier. My players really appreciate the new race (particularly the half-Vistani and Caliban) and subclass options, and the setting details (lore, deities, etc.) provide enough context to pique players' interests in the setting. The optional DM rules (e.g. Dark Powers checks, Sinkholes of Evil, etc.) and new magic items all help with establishing the ambience of the Mists and can easily be combined with the Curse of Strahd-specific rules.
The supplement is well written, and it's clear that a lot of thought has gone into the mechanics to make them fit with earlier incarnations of Ravenloft. A must for those interested in purchasing and converting the classic 2E Ravenloft adventures on DMsGuild, and strongly recommended for anyone interested in continuing their explorations of the Mists!
[5 of 5 Stars!]