Absolutely fantastic. Haven't enjoyed a dungeon this much since a Teenager playing ToEE or as a Uni student playing Rolemaster through LoTR Mine of Morioa. Nicely done folkls!

I'll start by saying I'm a big fan of Gillespie's megadungeons and own all of them in hardcover. So I was very excited to get this one. But I have to confess that I'm a bit disappointed with it. While it has some good elements, for me it just doesn't stack up to the others. I guess my expectations were too high. For one, the broader setting and backstory simply aren't as interesting. And while I understand the rationale for not mapping the whole thing, I have no desire to create a bunch of my own levels using geomorphs. I'm paying $65 or whatever for something I can just run. After mapping a couple levels, I just stopped. One can easily find complete Dwarf themed megadungeon maps on the Internet. Additionally, the room descriptions seem more vanilla than in Gillespie's other products. The rune stuff is nice, but this just doesn't grab me like the other ones and I find it far less useful in a modular sense as well. With his other dungeons, notably HighFell & Archaia, one can easily pull sections out to drop in anywhere. Not so much with this. So if you're really into dwarf-themed dungeons and don't mind putting in a fair amount of work to finish it, this could be for you. But it's less playable out of the box than his other dungeons.
Since you're here I'll give my personal ranking of all Gillespie's megadungeons:

1. HighFell
2. Forbidden Caverns of Archaia
3. Barrowmaze
4. Dwarrowdeep

All,

This module is a masterpiece. Do not be put off by the term megadungeon. It is usuable without having read the 336 A4 pages in advance.

I have been playing RPGs for 30 years and used/played about 100 published RPG modules. I almost always end up making material modifications to make them work (removing circus style different monsters and gonzo silliness that undermines dark ambience, cleaning up random 'no purpose' NPCs to motives/character etc).

This module was able to bolted on directly with internally consistent dwarf themed structures, monsters, maps, NPCs and backstory. I used everything.

Normally I shy away from massive maps. They tend to use up precious brain RAM that is better used to prepare for actual play/story/PCs. The rooms usually end up repetitive/pointless and all merging into a blob in my mind. Dwarrowdeep is the opposite. Each map is standalone and consistently themed, each room entry is succinct and unique. One read over an entry and then I just glance at it in game and we are on.

In an unexpected twist, the vastness of DwarrowsDeep has added to the wonder of explanation as PCs map on Graph Paper is starting to fill the table area. Going deeper and deeper...

Few modules achieve this standard.

Oliver