Bokafesh's Never Ending Dungeon, is a rather unique product. In over thirty years of gaming, I've not seen another product with this premise – it caught my eye. That alone makes it worth the price of admission.
The premise is rather neat. The dungeon begins with a finite size, and has certain properties. By exploring new areas, the dungeon grows. A new sector is generated (choose your options, or use a combination of the charts for inspiration or go entirely randomly selected features), and it retroactively changes all the existing sectors.
The adventure/campaign can be adjusted easily for anywhere from a single session of play to as long as an extended campaign. It was designed for a ninth level party, but has adjustments for lower and higher level characters. There are a number of plot hooks to ensnare our characters into the story.
Exploration will reveal the nature of the dungeon. The characters begin within their first sector, and interact with the environment and the creatures therein. At some point, they discover the connection between this sector and the next. The next sector may be similar, or perhaps radically different, and as an example could be a trade town. The thing is, prior to going there the original inhabitants did not trade with anyone, but having visited the trade sector, there is now a bustling trade between the two sectors – and that is the way it has always been. The retroactive changes won't be immediately apparent, but upon return to a previously visited sector differences will be present and potentially drastic.
I'd probably use this product as and side quest and nest it within another product, rather than run it as an entire campaign, but you could build an interesting setting off of the basis established within and expand it in interesting directions. I especially like that previously known facts can change with exploration, and that the new reality is how things have always been, as far as all the inhabitants of previously found sectors are concerned. That definitely has potential for an interesting setting.
The PDF is 40 pages, including covers, credits and the OGL, which leaves 36 pages of content. The PDF has been divided into sections, including an introduction, several charts to randomly generate a new section (or to use as inspiration to partially randomly generate your own), some premade sectors and information on the mysterious caretakers, and then NPC statistics. The document is well bookmarked, making it easy to navigate. The scans were done well, and the text and diagrams are easy to read. The writing and editing were excellent, as the product is easy to understand, and words are spelled correctly.
[5 of 5 Stars!]