Gorgeous graphics: utterly over-the-top color palette, like a black velvet painting. Very Edgar Allen Poe vibes. The enemies are terrifying. The music is very good, although I think the music volume is rather low. The defeat sound effect is absolutely sickening (I mean that in the best possible way).
Navigating the ballrooms and dining rooms is challenging but fair. The game has a variety of tasks without outwearing its welcome.
The ability to permanently incapacitate foes provides a welcome relief, but it also makes the game somewhat less scary than it would otherwise be; this is a trade-off.
I think the default mouse sensitivity is far too low, but since it can be increased in the Settings, this is a very minor point.
Note that, after I died and chose to return to the main menu, I could not activate any of the buttons. I had to quit the game to go another round. (Choosing "Restart" from the Game Over screen works fine.)