When working on my hex-crawl, the first thing I considered, even before designing the map, was how many encounters I should have per area. I looked at multiple sources and examined their suggestions. Of course, there is no singular method, and my findings were that encounter density—like most things—runs across a spectrum. At the sparse end of the spectrum, we have the classic methods from B/X and AD&D.
Basic D&D Expert Rules for Wilderness
The Expert book doesn’t offer much guidance on encounter density other than the map of The Grand Duchy of Karameikos. Examining that map, there aren’t many encounters. The bulk of the map consists of large areas populated by humanoids and monsters, but few hexes are indicated as specific encounters. Towards the center of the map are the human lands with the capital of Specularum and other settlements—mostly castles. These are still encounter sites because, after all, what are settlements if not human lairs? Fortdoom, for example, is even described as having dungeons underneath it. There are two other obvious encounter sites that are ruins: The Haunted Keep and Wereskalot. But that’s pretty much it. While it does have a section titled “Fill In Important Details and Points of Interest,” it doesn’t offer any guidance on how many. This is left entirely to the DM.
On a side note, the only area on the example map drawn out in further detail is a gnome lair. The vision of a party of adventurers dungeon crawling through a gnome lair as murder-hobos makes me laugh. More importantly, however, the material does not prescribe either of these things—whether it is dungeon crawling under Fortdoom or a gnome lair. All possibilities are up to the players—one just happens to be hilarious.
The rules section on Wilderness Encounters focuses more on wandering encounters rather than fixed sites. It’s worth mentioning that the map has about seven hexes per inch, indicating a huge space with very few encounters. This approach seems to seed just a few areas, allowing the party to wander if they are interested. If they do, the DM can roll on the procedurally determined wandering encounters. If something hooks the players, the DM can start preparing in that direction. This is only speculation, but the guidance in the book supports it. Section C under Designing a Wilderness states: “If the town and dungeon are placed near the center of a small-scale map, the players will be able to explore in all directions.” It advises just one dungeon and a nearby town, but also the freedom for the players to explore.
AD&D Dungeon Master’s Guide
The 1st edition of the AD&D Dungeon Master’s Guide offers more guidance. In Appendix B, after giving the table for randomly generating the terrain, it has another table for Inhabitation. It is a 1-100 table with different types of settlements plus ruins spread throughout the first 16 result numbers. Any result 17 or over is an uninhabited hex. Such a table yields results similar to the Karameikos map in that the points of interest are either settlements or ruins.
I suspect that the AD&D DM, like the B/X DM, is expected to either arbitrarily throw in a dungeon, lair, or odd discovery, or to use the wandering encounters rolled up during a session to inform what to make. Rolled up a couple of ogres last session? Maybe it’s time to place an ogre village with 2d10 ogres in it. How far away was the party from human civilization when the ogres were encountered, and where is that ogre village? What impact does that have on the going-ons of the nearby human settlements? The DM now has something to weave into the setting, and the world grows.
It is also important to note that this system suggests a 16% probability for one encounter. Sixteen percent equals approximately a one in six chance. So we now have a clue to encounter density: one per six hexes, or 1 on a d6. Where have I seen that before? Oh yeah, Shadowdark, in the Overland Hex Maps chapter: “For each hex, roll a d6. On a 1, the hex has one point of interest.” Shadowdark’s POIs are more fantastical than AD&D’s settlement-heavy take. I’m not sure when D&D adopted the Points of Light approach; it may have been third or fourth edition, but it was definitely post-1st edition where most encounters were settlements.
So now I have a starting place for encounter density: if I am to adapt the classic approach with sparse encounter sites, I will place them about six hexes apart or 1 in 6. To make it easier, I can roll a handful of d6 and place them at the 1s.
However, that’s not the only system I came across. I’ll be discussing those in an upcoming post.