This adventure is designed for 15-20 0-level characters or 8-10 1st-level characters. Remember that players should have 2-3 characters each, so they can continue enjoying the fun of play even if some of their PCs die off. In playtest groups of 15 0-level PCs, 7 or 8 typically survive. The author has playtested this adventure with groups of up to 28 PCs and experienced one complete TPK and several sessions with only a handful of survivors.That quite a estimated death count. Accurate give my experience with playtesting the DCC RPG.
In the comment section of James' post Chicago Wizards give this comment.
Something cibet said made me realize that the point needs to be made: DCCRPG is not D&D. It may be D&Desque in its pedigree, but it's not the same in "scale" or matched to any edition. It evokes similarities, but it's expectations and execution is/are far different.
The comment is spot on, despite similarities to the d20 rules and D&D it is own thing. I felt that Harley and Joseph succeeded in channeling 70s era fantasy. The potential weakness of the DCC RPG is in it's extensive use of charts and it will live or die based on how well they are presented.
The use of the extra zocchi dice is going to a minor issue in the long run. In the playtest I ran, Fighters and other classes improved their ability to critical by using a progression of dice that included the zocchi dice. Going off the top of my head, at 1st level you would get say a d8, then at 4th a d10, then later a d12, d14, d16, d20, etc. The bigger dice allow you to get better results on a critical.
There were a couple of negative comments on the need to have multiple PCs per player. Understand that you can still use the DCC RPG and play a campaign where the player starts out with a single character struggling to survive. If you use the adventures that Goodman Games has planned they will die as they are death traps, cool death traps but death traps none the less.
If you run your campaign in more naturalistic way, the character can avoid those type of locales and focus on the challenges they can overcome. Such has working their way up to the leadership of a bandit gang, or fighting a border war between two nobles. Slowly working up to the point where they can enter one of those death trap and survive. Nothing in the playtest ruleset precludes this style of play and there is a lot of interesting bits to the rules especially the magic system. You will soon be able to see for yourself after free RPG day when Goodman Games releases the beta.