8 Rules for Dungeon Improvisation

During my most recent pathfinder game, a number of my players were absent. Among them was the group’s sorceress, Phoenix Darkmatter. Her absence was particularly relevant because the primary quest of the party currently revolves around her. Without her there to participate, I assumed that the party would want to pursue some other goal, so prior to the game I prepared a number of quest threads in the town they had ended their last adventure in. True to form, however, they completely bypassed everything I had prepared. As I had predicted, they didn’t want to continue the arachnohomnid quest line without Phoenix, but they weren’t even slightly interested in protecting dwarven caravans either. No, this party of low level adventurers recalled hearing about a lich which lived in the southern lands, and determined that killing it would be an appropriate use of their time.

The rogue participated only under strong (and well justified) protest.

Fortunately, a random roll of the dice brought the party to their senses. After nearly being killed by a pack of wolves they randomly encountered while crossing the planes, they settled on a more reasonable goal: find out why the nearby forest was filled with half-ogre monstrosities. It’s a quest thread I had introduced in one of our first sessions. They had never seemed particularly interested in it before. I had to leave the room for a moment to find some of my older notes related to that quest–and what I had was not much. A mad wizard with ogre minions had taken up residence in the ancient elven ruins of Gorak Torar, where he was experimenting on transforming the local Gnoll population into Ogre-kin servants for himself. That’s all I had.

Oh, and the ruins were made of blue-white stone. Because this place was not at all a ripoff of Dire Maul.

The players asked intelligent questions and quickly found a trail of clues leading them to the ruins themselves. They’re starting to get too good at this game, I can’t rely on them fumbling about for too long while I find my bearings. It didn’t take them long after finding the ruins to gravitate towards the large building at the center, and make their way into the dungeon beneath it. A dungeon which I had absolutely no plans whatsoever for. So I improvised.

I’ve always prided myself on my improvisational skill, and everyone enjoyed themselves. It was easily the most fun I’ve had recently, and my players were still talking about the adventure a couple days later. Once the game was over, and I had a moment to review my performance, I went over my methodology for creating the dungeon, and retroactively codified 8 rules I had used to help me go about the task.

1. Steal. Do it rampantly, and do it shamelessly. Even if you were to completely rip off the layout of an environment your players were intimately familiar with, it’s not likely that they would notice. And if you change a room shape here, and add a few more doors there, a dungeon layout lifted from another game becomes completely unrecognizable.
2. Don’t make the dungeon fancy, just make it. Don’t waste a bunch of your time thinking about how to make things interesting, or how to create a theme, or complicated multi-room puzzles. You don’t have time. Draw corridors, draw doors, draw rooms, and figure out what’s in them. That’s all you have time for. If you want to add depth, do something simple like a locked door, or a key hanging on the wall. Then you can easily insert the matching element later.
3. Read -C’s PDF guide On Tricks, Empty Rooms, and Basic Trap Design. The Empty Rooms part is particularly important. Commit as much of this PDF to memory as you can, and use it.
4. While your players are discussing amongst themselves what they want to do in a given room, that’s your opportunity to figure out what’s behind all of the room’s doors. You don’t need to pay attention to everything they say, but you should already know what’s behind every door of the room they’re in.
5. You don’t need to worry about anything beyond the rooms which are adjacent to the one your players are in. There’s no need to waste time detailing a room which they might never even get near to. If you have spare time, focus your attention on adding details to the rooms you’ve already got. Something like a trap, a secret door, or some unusual monster or treasure adds depth to your dungeon.
6. Restroom breaks are a perfect opportunity to expand your map.
7. Select a small number of enemy types, maybe 2-3, and have those creatures constitute most of the dungeon’s population. Some rooms might have a special monster of some kind, but a small number monster types repeated gives the dungeon a sense of consistency. Don’t be afraid to put those monsters in a variety of situations, though.
8. If your players are looking for something in particular, it will not necessarily be along the path they take through the dungeon. They will likely pass a number of doors on their way through the dungeon, and it could easily be beyond one of those. If you’d like to handle this with as much agency as possible, roll a D6 each time the players descend to a new level. On a roll of 5-6 (or 4-6 for smaller dungeons) what the players are looking for is on that level of the dungeon. And each time the players enter a new room on that level, roll a D20. On a roll of 19-20, what the players are looking for is in that particular room.

These are just the rules I came up with off the top of my head during the game. I’d be curious to know if anyone else has similar methods, or tips on how I could improve my own!