Edit: I've thought about this more and I decided that I let my own bad experience push my review of the adventure lower than I should. I still believe everything else I have written, but I think that this adventure does work for what it does.
If you have a group of friends that you like to play with and you are all looking for the challenge, this will likely work well for you. But if you are going into a convention, there is so much variation that can happen with number people at the table and with party composition to make this adventure a fun romp or, as it was with me, one of the worst gaming experiences one may have.
Below is my original review.
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Even over a year later now, this still is the absolutely worst scenario experience I have played in. I blame part of it on convention staff, but in the end many of the problems are built into the scenario itself.
The scenario starts off with a bit on the challenge level of the scenario, but I find there are enough missteps within the scenario to make that warning itself misleading and pointless.
I was very much irritated to find out after our brief run into Bonekeep that it didn't scale for four players. This is ridiculous for a scenario that intends to challenge a party. It is obvious that what will challenge a six person party will be different from a four person party. Now, to the scenario's credit, it is meant to play as part of a special event with several tables to allow every table to be full for the run into Bonekeep. That is one place that I have to lay the blame for this experience at convention staff. I love you all for everything you do, but we don't know the scenario. When you saw a four person party with no idea of what was inside Bonekeep, you should have told us that it was meant for six person tables and that you were not scaling it down for us. I would have been fine with that, I would have found a different event. Instead you lead me to believe that this would be a challenge to our characters rather than the slog that it was.
For the half of the encounters, one class has it's damage dealing class ability negated. Our GM either accidentally also negated that same class ability in the first encounter or the adventure added that random immunity out of spite. Even in favor of the scenario, you shouldn't be negating any class ability that many times during a scenario. It doesn't make it challenging, it makes it either ridiculously hard if you have characters relying on that class ability.
Once I entered, I found myself bound to stick with the party until the rest of the party realized we couldn't handle this scenario. It was obvious to me following encounter 1. I couldn't leave though because other members wanted to continue forward. This is ridiculous for a special that will be gathering random groups of people into parties. I could have stayed by the entrance, but based on the murderous nature of the scenario, I felt like it would kill me as soon as we split the party.
Boring encounters. All the encounters I was exposed to were honestly boring. They were hard, but not hard in that I had to think of new tactics. They were ten to twenty round slug fests that just bored the hell out of me.
No roleplaying. I know, silly for this sort of event, but even bad scenarios can have some enjoyment created from basic roleplaying encounters. Since this one doesn't have them, it has to rely on the encounters being enjoyable. When the encounters fall flat, that leaves nothing fun about this scenario.
Encounters scale up poorly. The scenario spells out that we can leave any time, but with each encounter being so capable of killing any party member it feels so pointless. There wasn't a sense that we ran out of resources and couldn't keep going. Ever encounter was "wow, if we didn't get lucky there someone could have been killed." There was nothing we could do to gauge if we would be able to take on the next room.
Rewards metagaming. Almost all the encounters can be described as such. "Are you prepared for [blank]? If you are, then you beat the encounter!" All scenarios are like that to an extent, but this one seems to expect it.
This is only the first part. Because of the horrible experience with the scenario, there is none in this line I ever want to experience and in fact I will continue to warn people away from these series of scenarios in the future.
I can easily say to anyone I meet that given the option to play in any Bonekeep special or any other game, that they should go with the other game. The other game will be more likely to be fun even if they lose.