Ground Rules is a terrain generator for RPG hex maps. It creates hex by hex descriptions of hexes that include terrain, roads, rivers, settlements, and encounter sites. Ground Rules can be used to run a sandbox-style hex-crawl campaign, inspire campaign maps, or for solo play. Ground Rules assumes a fairly small hex size, five miles per hex is ideal.
To use Ground Rules you'll need some means of recording hex entries, ideally a paper or electronic hex map. As you build your map you'll be recording each terrain's contents, as well as a terrain code that's used to generate neighboring hexes. The basic process for generating a hex is easy. Each button in the table above represents a table used to generate part of a hex entry. To use the tables:
The most important rule: random systems are never perfect, especially when it comes to generating things like roads and rivers. Your judgement should always prevail over the dice. If you don't like a roll, ignore it or generate a new result.
Some feature-specific directions will ask you to roll dice to determine additional features of a particular hex. For your convenience a series of dice rolls are appended to each generated result. You can use these results or roll your own dice as you like.
Roads and rivers, collectively called paths, are hard to get right with a random system. Here are some rules and guidelines for handling paths using this generator.
Directions for roads and rivers (collectively, paths) are given as an entry point plus a route. Together they describe where the path start and ends. The illustration at right shows how to interpret these directions, depending on how you draw your paths and which hex orientation you use.
Directions have an entry point, which can be matched to corners or faces in the images. They also instruct you to count spaces. If your path runs along edges, begin at the hex corner that matches the given direction and count corners. The path exits at the last corner counted. If your path runs through hex faces, begin at the face that matches the given direction and count faces. The path exits the last face counted.
Hint: Draw rivers on edges and roads through faces for a clean-looking map.
Coastline, Shoreline, and some terrain features will ask you to place hexes of a specific type nearby. Common sense should prevail. If there are no empty spaces, or no locations that make sense, feel free to ignore these directives.
Be sure you note the terrain code for each placed hex. You should also generate a Locale entry using that code to see if there are any special features in the new hex.
Coastline marks a transition from land to ocean terrain. If the generator produces a Coastline result, do the following:
Shoreline is the reverse of Coastline, marking a transition from ocean to land. If the generator produces a Shoreline result, do the following:
Here are a few ways to change up how you use tables.