Discovering the Dungeon
See the companion post with a play report here.
I've been thinking a lot about procedural generation recently and trying out a few systems of my own design. I put out one example earlier this year using cards as the main driver, but I also have a much bigger project in the works that uses a more traditional series of many dice rolls. I also recently got into reading the Delicious in Dungeon manga, and I've been itching to run a proper big old dungeon. But, since my home group is happy in our Not Enough Scoundrels Mothership campaign, I decided to do some solo dungeon play.
At first, I toyed with the idea of adapting one of the systems of procedures I've already been working on. But, those are for sci-fi, and it would have taken a lot of writing to adapt them to generate the things you expect from a dungeon instead. Then, I remembered the AD&D 1E DMG has a pretty robust dungeon generator Appendix A, and when I went to check it out, I saw it even had some brief guidelines on how to use it for solo. So, I set out to use it to run a solo dungeon.
Since I've played AD&D 1E before though and didn't like how complex the characters are in that game, I decided to run my play with OSE and only use Appendix A for generating the dungeon. This has ended up with a bit of mish-mash of the procedures from the two games, along with some tweaks of my own along the way, and at the request of Amanda P. when I posted about this on Bluesky I'm writing up the procedures I'm currently using in play. There's also a companion post with a play report including commentary on how the procedures generated the story that played out for my first character.
The Procedures
The Appendix A dungeon generation procedures are worth reading on their own in full, and I'm not going to describe them in detail here, but I'll give a brief summary with a focus on how I've been modifying them for my own solo play.
The core of Appendix A loop is a table called the "Periodic Check" that you roll when moving down a passageway to determine if it simply continues, turns, or has another feature, such as a door, room, stairs, trap, or side passage. You roll this whenever entering a new passage, every 60 ft. moved through a passage, or, in some cases, 30 feet after having encountered another dungeon feature. My one change to this was to remove the result of a wandering monster on 20, since I'm using the OSE procedure to check for wandering monsters every 2 turns, and have tricks/traps appear on a result of 19-20 instead.
Flowing down from the Periodic Check, there's a series of 7 other tables, one each for each of the possible results on the Periodic Check -- doors, side passages, passage turns, rooms/chamber, stairs, and tricks/traps -- as well as a table for caves and caverns for the lower levels. Many of these are then expanded with subtables for more specifics, the greatest being 10 subtables for defining everything about rooms/chambers--shape/size, number of exits, contents, and some specifics about the contents. The one thing I've added here is a procedure for determining if doors are stuck or locked since that's oddly missing from the Appendix A tables.
Lastly, while Appendix A calls for using the AD&D dungeon encounter matrix and has a treasure table for treasure in the rooms, I've been using the OSE dungeon encounter table, mixing in some ideas from The Monster Overhaul where I can, and using monster-specific treasure where it makes sense.
Apart from that, I've been following the stock OSE procedures for exploration and wandering monster checks, and using the x-in-6 chances for things like noticing or setting off traps, finding secret doors, listening at doors, or opening stuck doors. I generate the passages and rooms, and have turns pass based on my movement rate and actions, and carry on room to room. I'm of course also using the reaction roll for monsters so that it's not just a fight all the time, and using ability checks sparingly for things like trying to race through a room and avoid combat.
One minor adjustment relates to the check for opening a stuck door, and similar situations where a character might make enough noise to alert monsters. While per the OSE rules this just alerts monsters on the other side of the door, I've been making a wandering monsters check in those situations.
This has all worked well so far through three sessions and 9 rooms of the dungeon. I'll make update posts as I play more and possibly figure new things out.