Random Wilderness Generator (RWG)
The Random Wilderness Generator is a tool designed to assist dungeon masters in creating outdoor settings during gameplay, whether as an unplanned starting point or as a means of introducing environmental randomness. It serves as a useful resource for solo play and for developing a DM's improvisational skills. When using this generator, the initial location of the player characters is always in a remote wilderness, far from habitation or infrastructure, with the exact distance from civilisation unknown. The nature of the starting hex is determined by terrain steepness, hydrography, vegetation and climate. These factors influence both the level of threat to the players and the natural resources available, allowing them to engage with and learn about their surroundings.
Contents
Unlike the structured confines of an underground dungeon, the wilderness is a vastly more complex and unpredictable environment. Achieving even a basic sense of realism cannot be done with simple die rolls alone. While a fully simulated world could be created using advanced computer algorithms, such an approach would limit a DM's ability to make spontaneous adjustments, shift results as needed or observe the step-by-step creation of the setting in real time.
Instead, this generator balances complexity with flexibility, using a structured system of tables to determine key environmental factors. Though consulting multiple tables may be necessary, this generator is intended for world-building rather than real-time gameplay, allowing time to study and refine the setting as it develops. Links to this page, and to other dungeon generation resources within this wiki, will include the "RWG" designation and will be categorised under "Random World."
Terrain
Because the shape of the land influences nearly everything else in the environment — determining where rivers and lakes form, what kinds of vegetation can grow and what creatures can survive — it must be established first. The suitability of land for settlement and its usefulness to inhabitants also depend on the terrain's relief, which describes the heights and depths of landforms in relation to each other and to sea level. For this system, each hex represents an area approximately 38 square miles in size, with a diameter of 6⅔ miles.
| 1st roll | variation (ft.) | type | description | next hex adjustment | cluster size | |
|---|---|---|---|---|---|---|
| up | down | |||||
| — | 0 | sea | coastline passes through multiple points of the hex; see note below. | 01-30 | — | — |
| 01-02 | 50 | flat | level, lacking undulations or slopes, with slow water drainage. | 01-06 | 91-00 | — |
| 03-08 | 100 | rolling hills | gentle to moderate, with occasional variations in elevation. | 01-09 | 87-00 | 6-18 |
| 09-32 | 200 | undulating hills | moderate to high slopes, with notable changes and gulleys. | 01-12 | 83-00 | 5-15 |
| 33-70 | 400 | foothills | significant dips and rises, with irregular steep slopes and low stretches. | 01-14 | 79-00 | 4-13 |
| 71-85 | 800 | rugged hills | commonly steep throughout, with rock outcrops, narrow valleys and uneven level areas. | 01-15 | 76-00 | 3-12 |
| 86-94 | 1500 | rounded mts. | abrupt slopes and bluffs, with rounded peaks, rocky ridges and ravines. | 01-16 | 73-00 | 3-10 |
| 95-98 | 3000 | mountains | dramatic rocky ledges, with rugged cliffs, canyons and sparse vegetation. | 01-17 | 70-00 | 3-9 |
| 99 | 4500 | craggy peaks | precipitous climbs, jagged peaks, rock faces, deep gorges, absence of vegetation. | 01-18 | 67-00 | 3-8 |
| 00 | 6000 | alpen | sharp ridges, sheer rock faces, glaciers and snowfields, constant winds. | — | 63-00 | 3-7 |
The 1st roll is only made when first entering the generator, determining the general terrain in which the characters begin. The probabilities assume the characters have emerged from a subterranean lair or dungeon, which are most commonly found in undulating hills, rugged terrain or foothills. This roll is only needed at the start, unless the players are teleported or pass through an astral gate, re-entering the generator in a new location.
Variation represents the difference between the highest and lowest points in a hex. The precise elevation does not need to be known; this measurement helps the DM visualise how steep or rugged the landscape appears. Since it is a relative measure, it does not refer to height above sea level but rather to changes within the hex itself.
Type of a hex determines the general character of the land, affecting the terrain features found there, while its description provides an approximation of common landforms such as slopes, depressions, bluffs, ledges or cliffs. Specific details — such as where these features are located within the hex — are left to the DM's interpretation when presenting the landscape to the players.
Next hex adjustment is used when the party moves into an adjacent hex that has not yet been generated. A d100 roll determines whether the new hex maintains the same terrain type or changes in variation. If the players have an elevated view that allows them to see into an ungenerated hex, the roll can be made in advance. This adjustment is based solely on the hex being left; previously generated hexes beyond that one do not influence the result. If the roll falls between the "up" and "down" thresholds, the terrain remains the same.
- For example, if the party leaves an "undulating hills" hex and moves into an ungenerated one, a d100 is rolled. A result of 12 or lower increases the variation, turning the next hex into "foothills," while a result of 83 or higher decreases it to "rolling hills." If the roll is between 13 and 82, the new hex remains "undulating hills." Some optional rules allow for rare, dramatic shifts in terrain — a roll of "01" might increase variation by two degrees, flattening hills into plains, while a roll of "00" might decrease variation by two degrees, shifting undulating hills into rugged terrain.
- The next hex adjustment system is designed to prevent abrupt terrain shifts, encouraging the formation of large, continuous landforms. If desired, the likelihood of rolling sea hexes can be adjusted based on campaign needs — reducing the frequency for land-based campaigns and increasing it for an island-based setting. Additionally, a river or stream gives a +8 modifier to the next hex roll, encouraging landforms that support flowing water.
Cluster size determines how many contiguous hexes of a terrain type must exist when a new type is first generated. When a new terrain feature is rolled, 4d4+2 hexes must be designated as part of the same landform, ensuring that geographical features appear as large, connected regions rather than isolated pockets. If subsequent rolls do not naturally generate the full number of required hexes, the DM must override them to ensure continuity.
- For example, if rolling hills are generated within a flat plain, a roll of 4d4+2 determines that at least that many hexes must be designated as rolling hills. If further rolls begin introducing new terrain types before the required number is reached, those results must be disregarded until the full cluster size is met. This system ensures that large-scale landforms develop naturally, rather than appearing as random or disjointed features.
- Because multiple clusters may emerge in close proximity, new hex rolls may determine which cluster a hex belongs to rather than simply adjusting terrain based on the last hex exited. Though this system requires careful tracking, consistent note-taking and planning make it manageable. If a terrain cluster is interrupted — perhaps by a body of water or another dominant terrain feature — the lowest-variation cluster should always take precedence when determining how the map develops.
Initial sea hexes introduce coastlines, which can either be placed for convenience or determined randomly. Once the first sea hex is established, the placement of additional coastline hexes becomes more constrained, limiting where new land-water transitions can appear. Small, enclosed saltwater seas may form inland, depending on the rolls. Beyond the coastline, further sea hexes are treated as open water, requiring no further land placement unless additional coastlines are generated.
Vegetation
The natural biome of a setting, layered atop the terrain, plays a crucial role in shaping the environment and the challenges adventurers will face. It affects movement and line-of-sight visibility, determines the types of wildlife and monsters that inhabit the area, influences the availability of resources for supply and shelter, and establishes the prevailing climate conditions. In this campaign, the setting is modeled after a European environment, with vegetation types limited to those naturally found on that continent. This restriction also defines the range of possible climates, as certain ecosystems cannot exist without the appropriate temperature and precipitation patterns. The campaign begins on May 1st of the Earth calendar, allowing ample time for characters to prepare for the coming winter, securing provisions and shelter before harsher conditions set in.
| 1st roll | type | description | Köppen climates |
|---|---|---|---|
| 01 | alpine | low-growing plants adapted to gravelly soils, including sedge, moss and lichens, found above the treeline. | H |
| 02-03 | arctic | little or no vegetation due to extreme conditions, snow cover and the lack of nutrients for plant growth. | Et |
| 04-06 | dry forest | mixed seasonal and non-seasonal deciduous trees with varying undergrowth, adapted to dry or hot climates | BSh, Csb |
| 07-41 | forest | north temperate mixed conifers and deciduous trees, with dense undergrowth | Cbf, Daf, Dbf |
| 42 | heath or moor | treeless landscape with low-growing shrubs, grass and mosses, peat or heather, with occasional bogs. | Cbf |
| 43-58 | macchia | drought-resistant Mediterranean, tough shrubs and widely spaced trees, adapted to hot climates. | Csa, Csb |
| 59-63 | steppe | vast expanses of grassland with sparse tree cover, transitioning between forests and desert landscapes. | Bsk, Csb |
| 64-75 | taiga | sub-arctic dense needleleaf conifers, with minimal undergrowth | Dbf, Dcf |
| 76-77 | tundra | low-growing plants with a short growing season, associated with permafrost; trees cannot grow. | Cbf, Dcf, Ec |
| 78-80 | wooded steppe | short grasses with drought-resistant trees, without undergrowth; transition between steppe and forest. | Bsk |
| 81-00 | woodland | broadleaf hardwood trees, shrubs and meadows, with much undergrowth. | Cbf, Dbf |
Climate zones span hundreds of thousands or even millions of square miles, dictating which types of vegetation can exist and ensuring that variations within a zone are rare. While microclimates do occur, they are extremely uncommon. Any shift in vegetation must align with terrain changes already established through additional die rolls. Elevated terrain, such as areas above foothills, lowers the temperature and may alter the climate classification (e.g., from Cbf to Dbf), potentially impacting vegetation as well. However, in most cases, the initially determined climate and vegetation remain the default unless the characters travel at least 30 hexes in a straight line, at which point a natural shift in climate may be expected.
The 1st roll establishes the dominant vegetation of the entry hex and does not need to be rolled again except under exceptional circumstances.
Köppen climates can be determined with a simple die roll, categorising the world's climate types based on temperature and precipitation patterns. These classifications include broad categories: "A" (tropical), "B" (dry), "C" (temperate), "D" (continental) and "E" (polar). Additional refinements describe seasonal variations: "a" (hot summer), "b" (warm summer), "c" (cool summer), "f" (humid year-round), "h" (dry winter), "k" (dry year-round), "s" (warm dry summer) and "t" (cold year-round). The designation "H" is used for high-altitude regions where standard classification breaks down due to elevation and latitude effects. More details on these classifications can be found on this Wikipedia page.
For climate generation, I refer to this historical database, identifying real-world locations that match the generated vegetation, terrain relief and climate type. Selecting a specific year, such as 2018, and a date like May 1, provides an approximation of what the weather conditions would have been at that time.
Taiga-based settings are characterised by cold temperatures throughout the year, severe winters and an environment dominated by large fauna and formidable predators. These lands are home to gnolls, bugbears, trolls, giants and winter elves, who have historically prevented widespread human settlement. The scarcity of permanent habitation leads to a diet primarily based on hunting and fishing, supplemented by wild oats and other foraged foods. Travel is difficult due to the vast stretches of dense forest, boggy terrain and wide, shallow rivers. Trade by sea is rare, as the coastal waters remain arctic in nature, and maritime activity is largely limited to the shipping of timber, furs and fish.
Intent of the System
The prioritisation of continuity is intentional. Terrain variation is managed in a way that prevents abrupt shifts, and climate changes occur only after meaningful travel distances. This prevents the kind of disjointed hex transitions that often plague random world generators. The concept of cluster sizes strives to ensure that terrain features emerge in natural groupings rather than appearing in isolated, unrealistic pockets. Admittedly, complexity is a condition to be overcome, demanding a structured approach to record-keeping. Some dungeon masters may find it beneficial to develop a reference sheet or shorthand notation to manage clusters effectively.
