[An OSR Pattern] One, Two, or Three Exits

This is an OSR Pattern. If you haven't read one of these before, scroll to the bottom of the post for some context.

One, Two, or Three Exits

A room with one exit is a dead-end; with two exits: a waypoint; with three exits: an interesting choice. Four or more exits is fatiguing.

Sometimes, you'll see a dungeon room that has way too many doors:

The Temple of Elemental Evil (1985)

This is uncomfortable for both the Referee and Players. For the Referee, they have to communicate too much information at once. For the Players, they have to comprehend too much information at once, and the pacing is ruined as the Referee describes 7 different doors (excluding the one you entered through, presumably).The excess will also surely mean the Players will ask for clarification now or later.

People can hold 1-3 pieces of information in their mind at once. This is true for NPCs. It is true for quest hooks. And it is true for dungeon rooms. When placing exits, do so deliberately to manage cognitive load and create pacing.

A room with one exit is a dead-end. This is...

• A cognitive break, as the Players have reached a terminus.
• A tactical nightmare (no escape) or a fortifiable position (no sneak attacks)
• An invitation to search for secret doors ("really? there are no exits in this room?")

A room with two exits is a waypoint. This is...

• A passage or hallway. Adding interactive elements to a route complicates the keying process as it requires you to number or letter a hallway, in addition to the rooms. To avoid this, make the hallway "a room" and as interactive as you please.
  
• A pitstop, as the Players move forward with purpose.
• A non-choice, which provides the Players with a mental break ("only one way to go from here").

A room with three exits is an interesting choice. This is...

• Only true if the Players can learn something meaningful about the two paths before them. Choosing between a wooden door and a wooden door, or even a wooden door and an iron door means nothing.

A room with four exits is a hub. This is...

• A crossroads to which you will likely return.
• A place to sit, smoke a pipe, and consider a while.
• Difficult to hold in mind all at once.

All of this applies not only to rooms, but also points in the wilderness or sites in a settlement—anywhere that is composed of nodes and lines.

A Bastionland borough

Therefore:

Create rooms (or sites, or nodes) that have one, two, or three exits. If you must, make a hub with four exits— but no more. This improves pacing and manages cognitive load for all.

***

Favor SIMPLE ROOMS, but give them DYNAMIC TERRAIN . Pair with CLUES OF THE ROAD AHEAD to make route choice meaningful, not arbitrary. If your design would benefit from four or more exits, you may want to GIVE THEM THE MAP.

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Context

Dungeon Merlin inspired us to articulate OSR adventure design practices using the structure of A Pattern Language.

A Pattern Language (1977, by Christopher Alexander) is not an RPG book. It's a toolkit to help people create physical places, like neighborhoods or home, that feel alive and human.

To do this, it articulates 252 patterns. These are physical motifs listed from macro ("The Countryside") to micro ("Paving with Cracks Between the Stones") and all reference other patterns, creating a web of connections and themes.

If this is difficult to picture, just read one. Here's one of my favorites: #159 Light on Two Sides of Every Room.

All of the patterns are presented using this template:

• A brief introduction
• A problem statement
• An elaboration of the problem.
• The solution statement— stated in the form of an instruction.
• A list of related patterns

The authors also rank their solutions, using stars. "**" is "Our solution is probably the best way to solve this problem". No asterisks is "There is probably a better way to do this—but we haven't thought of it yet." You have to respect the humility.