I ran the third adventure in Book of Crypts on Friday: The Dark Minstrel.
This is one I used to run all the time, largely because it is easy to do even if you don't have the book once you know the information. So if I was at a friends house and we all wanted to play D&D but I didn't have my Ravenloft material, this adventure was a good option.
The basic premise is quite simple. The players arrive in Claviera where they receive an invitation from Baron Lyron Evensong to attend a banquet at his mansion. Once there they feast and then are brought to his study where he plays a song for them on a harpsichord. After finishing the song, he explains that they are all trapped in the room for the next 100 years (and investigation confirms that the room is surrounded by void). The Baron doesn't want to hurt the party, he just wants them to keep him company for the 100 years night. They soon find out he is a spirit, and seemingly impossible to defeat. The players must find the Baron's weakness so they can defeat him and escape.
I quite like the premise and basic structure of the adventure. Playing it again, even decades later, I still really enjoy this aspect. It essentially takes place in a single room, so it is role-play heavy and an extremely confined investigation. The players can learn more about the situation by talking with the Baron, by reading the books on his shelves and studying features of the study. It isn't particularly difficult, I've never had a party that failed. But it is still quite fun.
The Baron is a pretty interesting character and I am realizing it fits a pattern so far with the adventure: many of the villains see themselves good and the designers take pains to create moral grayness within the parameters of the objective D&D alignment system. Obviously this is true for lots of evil NPCs, its just clear there is a conscious choice to play with this aspect of alignment in Book of Crypts.
This was always an interesting feature of Ravenloft. You can't detect Good or Evil in the demi plane, but good or evil still exist as part of the alignment system and cosmology.
Baron Evensong is something of a musician vigilante, seeing himself as extremely moral, to the extent that he acted as judge, jury and executioner for transgressions he perceived in others. He is a very enjoyable NPC to play. He sees himself as Lawful Good, when in reality he is Neutral Evil. I thought this was a good use of an alignment system that can break down under scrutiny (describing an NPC as NE but who stating they believe themselves to be LG is an easy feature to latch onto when running the character). In that respect he is walking a similar line to Dante in Blood in Moondale (a vampire who is presently CN and striving to be good by not drinking the blood of people, but rather drinking animal blood), and Victor Mordenheim as well.
The adventure itself is very well done in terms of providing lots of things for players to do. The bulk of the investigation revolves around the book shelf (though other clues exist) and I rather like the system for dealing with it which is as follows:
If the players roll anything but a 9, 10 or 11, they find books that might be interesting but don't help with solving the adventure. It generally takes an hour to skim through a given volume. If they roll a 9, 10 or 11, then they discover books such as the Baron's personal journal, a book of his poems and a book about imbuing musical instruments with magic. All of these three categories of book provide crucial details for solving the adventure. There is a similar section in the adventure dealing with sculptures in the room.
The riddle to solve is that the Baron's spirit is tethered to his harpsichord due to a spell he had cast upon it that went awry. If the players destroy the harpsichord, the mansion crumbles and they are freed.
By far this was the easiest adventure to run in the book to this point and I think it very much has to do with the simplicity of the adventure premise and the how easy it is for the GM to manage the clue finding (due to how it is organized and how elegantly it is presented).
All that said, there are some issues with the module, as with some of the other adventures around railroading and heavy handedness. Here is a good example of one such moment. The invitation the players received was cursed and whoever read it suffers phobias that do psychic damage until the players go to the mansion:
And the introductory hook is especially difficult for the party to avoid:
It is very evocative, and I like the way they bring music into the players being drawn into Evensong's domain, but it may be a concern if you want the players to have more freedom to choose not to go on the adventure or to approach the adventure from different paths. However, for monster of the week style play, I think it works well. I just made a point of telling my players in advance that these adventures would be run in a different style from my usual approach to play.
I did find a notable typo in this adventure where the Baron's name is misspelled in a key header, but otherwise it was free of any errors I could discern. I do recommend this adventure with the above caveats. I think it is useful for GMs to help them develop certain skills. Running an NPC in a room with the PCs for an entire adventure is much easier than it sounds, but it is probably something people might find daunting or challenging at first. Luckily the Baron is stark enough that I don't think this is much of an issue, and the Baron has a strong built in motivation (to keep the PCs as his guests to ward of loneliness and boredom) and the players have a strong enough built in motivation (to escape the Baron's curved room so they don't die of old age), that I think it is fairly effortless.