Absolutely LOVED reading and playing this! The Abyss in particular is amazing -- just so fun to read and watch the players try to puzzle out its mechanics. The writing in this whole module is so, so good. I often had to restrain myself from revealing too much detail because I wanted to share the writing with the players. As someone else commented below, the sort of asides/extra details that are for the DM's eyes only really made this extra fun.
I DMed this for a party of 3 who started with level 1 D&D characters, and allowed them all one backup character, which 2 of them ended up using. It may be that their characters were a little too optimized for the dungeon (could walk on walls, high ACs) but I found myself adding extra damage + health dice to enemies. This was also my first time DMing, so I didn't realize how much detail I would need to make up myself regarding enemy stats. If I was a more experienced DM I'm sure it would've been fine, but I found it stressful to try to judge what bonuses made sense to add to monsters' attack rolls, saving throws, etc. without that written into the module. Once the party hit room 21, they did a lot of backtracking around the rest of the dungeon that ended up costing heavily. I did offer checks in place of some instakill effects.. with mixed results lmao.
Also, one small typo -- in the table of contents, Floor 4 is written twice instead of Floor 4 -> Floor 5. :)
Thanks so much for sharing this module in the bundle for racial justice, and I'm looking forward to playing more of your work!!