Prevent maps from ruining your dungeons!
Did you know the early editions of D&D had chase rules? Your characters would lose track of positioning, direction, and could get seriously screwed if whatever was chasing them backed them into a corner. It’s hard for us to imagine. After all, if you have a map out in front of you, how do characters not just retrace their steps or lose positioning in the first place? I don’t know how the original games handled it exactly. I suspect folks using these rules didn’t allow players access to maps unless they themselves were making the maps. It’s a solution, but it only works so long as the GM remembers and enforces the implementation. I’m not a fan of those solutions, I prefer my games to work regardless of whether the GM decides to keep their foot on the gas.
With those thoughts in mind, I came up with a solution some time ago while discussing monster ecologies and their impacts on playstyle. At the time, the BROSR folks said dungeons were defined by colliding ecologies, with lairs and insulated ecologies within. A dungeon could have a garrison of hobgoblins, a nest of hook horrors, a dragon’s lair, and more all being raided on occasion by drow from another subterranean locale warring with a pod of aboleths. These in turn were all subject to trade, harassment, or any number of other diplomatic or hostile interactions from wandering monsters and adventuring parties. Furthermore, these elements can be added, duplicated, replaced, or removed nearly at will. What makes a true dungeon is whether it can be restocked, whether the subterranean home of adventure is properly suited to receive encounter fodder from a multitude of ecologies and factions. For that, the real breadth and depth of the dungeon must be too large to map out. This is the ideal environment for a location which lives and breathes, which supports expressions of play and encounters which rely on the party not knowing exactly where they are.
The delightful news is this doesn’t actually restrict you from using maps. You can still mark out terrain from room to room, but with the understanding it doesn’t represent the entirety of the dungeon and delineating where these unmappable regions begin. So, here’s my solution; divide your dungeon into mapped and unmapped regions.
Mapped regions are of relatively constant shape and form, the kinds of areas for which maps are actually useful. These are where rooms resembling geometric shapes get to live in harmony. They tend to feature:
Stable cave formations.
Stable mineshafts.
Ruins of ancient civilizations.
Recent construction.
Unmapped regions are too inconsistent and topographically irregular to be properly mapped out. These areas are the best suited for chases, and any other encounters in which the party’s position relative to the rest of the dungeon is best left unknown or vague. Unmapped regions are in flux due a mix or even all of the following factors:
1. Natural disasters:
Volcanos.
Earthquakes.
The world below collapsing inwards.
2. The engineering and warring of opposing factions:
Building forts.
Digging tunnels.
Damming rivers.
3. Relatively Natural Phenomena:
Rivers (whether water or magma).
Megaflora moving sediments through their growth and movement.
Megafauna doing the same.
The living rock of the world below shifting.
ALL of the aforementioned collapsing and compacting themselves.
Now, you may be thinking the distinction between a mapped and unmapped region is relative, if not arbitrary. I don't think it's arbitrary, but you would be right in thinking it was relative. Who's to say which levels are or are not mapped and unmapped don't change from session to session? From delve to delve? Well, clearly the game master is. If they decide to change the status of given levels from mapped to unmapped and vice versa, a single dungeon could multiple methods of adjudicating the delve, of playing through the delve, of exploring the dungeon, and of supplying and restocking encounters from session to session.
Just as Gygax intended.