Immersive Ink

Is the hyphen after "offshoots" meant to just separate the sentence? Wanted to be sure that, and the ellipses at the very end were purposeful. Instead of the hyphen between "offshoots-sprawling" maybe do something like "a dozen or more levels, sprawling haphazardly in all directions, with various offshoots, rather than stacking..."

Some of my other suggestions below, hope they help:

Before players can begin campaigning in delve into the Underworld the referee must can (or maybe keep MUST here, instead of CAN) secretly draw a (secret!) map of the mazy dungeons on graph paper.

There is no limit to the number of levels and sub-levels a dungeon can have, nor any size restriction on these levels. Ideally, a dungeon should have a dozen or more levels down with various offshoots-sprawling haphazardly in all directions rather than stacking neatly atop one another-with each. Each level being progressively more difficult and more rewarding than the last.

The referee should outline several levels at a time, noting how they interconnect by stairs, trapdoors, chutes, chimneys, sloping passages, or even by teleportation gates. Each should offer various opportunities to descend (or ascend) in order that players not be too constrained. Conversely, the most notable features and richest treasures of the dungeon should be relatively difficult to locate. The lowest levels should always include means of egress to exploring yet deeper depths.

Thanks @rredmond. That hyphen was actually an en-dash, but it should have been an em-dash.
The prose is partly an attempt to echo the early Gygax style, but I do agree that section was too impenetrable. I've pulled it back from the brink, thanks

Ha hah! Just suggestions of course. Ignore it all and no biggie! When I used to help Jim Kramer he used semicolons as colons it used to drive me crazy, but he taught me well about the author’s voice. I ain’t a great editor but I’m a pretty good suggester!

PS: and dashes and commas (Oxford or otherwise) are NOT my forte!

Next up, we have:

(Underworld) Distribution of Monsters and Treasure

Those monster tables coming next...

Next up:

(Underworld) Monster Tables

Next up:

(Underworld) Treasure Table

Rounding out the Preparation for the Campaign chapter, next up we preview

(Underworld) Tricks and Traps

Based on the high word count dedicated to this topic, perhaps it was one Gygax's thought more about?

Comments welcome!

Look at that progress...

Thanks Mike. Yeah, I am pretty happy to have pushed through the whole Preparation for Campaign chapter in a month and a bit.

At this rate, there's a risk I might finish it!!