Dungeoneers Black Book is a 55 page adventure supplement for Mork Borg. And it commits with resolute force to the Mork Borg bit. Every page is striking and unique, and the tone is garish and gloomy and weird.
There are 16 dungeons in the Black Book overall, enough for months of oneshots. And while they're all fairly bite-sized, they each feel extremely distinct.
The most similar are the handful of caves, which are different more in theme than in structure, but there's also a lot of dungeons here that are experimental without losing their gameyness. The Dusty Catacombs is built out of cards, and this allows you to make it as big or as small as you want (within an overall cap of 52 rooms and corridors.) Dr Grigory's Laboratory Warren uses words as map pieces, so a hallway will be written as CORRIDORCORRIDORCORRIDOR, and this is a little tough to describe, but visually it's quite striking.
In terms of difficulty, everything feels calibrated for a standard Mork Borg party. The expectation of lethality is there, but it's consistent with the tone and feels earned, not forced.
Overall, if you like Mork Borg as presented in its core book, there's something here for you. And if you like gorgeous art and layout, there's definitely something here for you---every spread is a painting.