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.