Overall, this adventure is pretty well designed. The dark theme was wonderful for a halloween one shot. My group generally had a good time; the encounters were all fun and unique, and each room of the dungeon adds to the story in a meaningful way if the players poke around a bit. However, there is one encounter near the end that I don't appriciate the design of. Normally, it woundn't be a deadly encounter whatsoever. Its purpose is to guide the players up the platform in the middle of the room to the bossfight. There is one complication though: if the players put out the candle the NPC is holding, the floor comes to life and "bludgeons them into unconcioussness." No saving throw. No reactions. It's a very "rocks fall, everyone dies" moment. The module does provide some variants, in case you don't like the encounter, or want some more combat in your adventure, but it does not make it very clear that these options are available, nor how to implement them. If you're planning to run it as written, then beware.