The Implied Setting

The implied setting refers to the campaign environment suggested by a given ruleset. Put another way, it’s the arena wherein the rules get played out. Simply put: If it’s in the setting, there must be a rule to arbitrate it.

This isn’t to say that such rules must be complicated, and this tends to hold up for most OSR games, which favour “rulings over rules” (i.e., players and Referees are encouraged to follow the spirit of the law rather than the letter). We’ll start digging into the OSR implied setting through the lens of the Principia Apocrypha, perhaps the best summary of what Old-School Renaissance play is all about. Of particular interest to our goals are these OSR tenets:

• Open World: The setting contains varied environments and challenges through which characters freely pursue their goals, which can be altruistic or self-serving; players have free agency over their character’s actions, which ultimately serve to guide the setting’s development as Referees create encounters to facilitate the players’ priorities.
• Exploration-centred: Characters are encouraged to advance in level, usually through the accumulation of experience, which is very often quantified by treasure value; acquiring gold is how a character becomes more powerful in the setting.
• Random: Referees are encouraged to build the setting using random tables, which has the immediate advantage of saving time and the auxiliary benefit of driving innovation through the integration of unexpected results.

In its most basic form, the implied OSR setting needs to accommodate searching for treasure, wherever and however the players want their characters to do so. To make it fun, the Referee must set engaging challenges before the players. The more powerful the players’ characters, the better their chances of navigating and overcoming these challenges.

Truth told, this describes a lot of TTRPG settings. In the World of Greyhawk, characters search for treasure so they can become powerful enough to search for greater treasure. The Forgotten Realms are similar, though with arguably more world lore cohesion. Dark Sun had a rich history that created present-day challenges, but under the hood it was about searching for treasure in a post-apocalyptic desert world. Same with Spelljammer (searching for treasure in space), Eberron (searching for treasure in a magitech world), Mystara (searching for treasure in a high-magic world), etc.

But while these examples all support the core goal of character advancement through challenge, the nature of those challenges revolve around a world-spanning theme (post-apocalypse, space, magitech, high-fantasy, et al.). These settings actively spell out the conditions for play—there is little, if anything, implied at all.

The B/X Implied Setting

The Cook, Marsh, Moldvay version of B/X D&D, published by TSR in 1981, suffers no such limitation, possibly because it had no official setting until the publication of the adventure module X1: Isle of Dread. And even then, that setting was only sparsely introduced.

Isle of Dread included a brief overview of the Known World, and many of the places described came from author Tom Moldvay’s own campaign, co-created with Lawrence Schick. These entries are great examples of the OSR mindset at work: brief, conceptual, and thematic, they provided enough information for the reader to imagine—correctly—who lived there and what went on, but they were so happily lacking in detail that the reader could simultaneously imagine—with equal clarity—their own how’s and why’s.

This approach suits the OSR Implied Setting model perfectly: Instead of starting with world hooks (like in Greyhawk or Dark Sun, for example), the implied setting starts with the rules. Think of it as reverse-engineering: The rules describe such-and-such a condition and we, as Referees, are tasked with creating an environment whose history justifies that condition.

And, when you read carefully, the B/X rules establish a great many conditions. For example, character race is synonymous with character class, so we must consider what it means for humans to have their choice of four classes while demi-humans have only one. The rules tell us that 1st-level clerics cannot cast spells, though the efficacy of divine magic “proves” the gods are real. We know that characters are meant to explore ruins for treasure, suggesting past civilisations who were not only prolific builders, but also wealthy. The standardised coinage and existence of a “common” tongue implies a level of social cohesion. The 3-point alignment axis packages the struggle between Law and Chaos as borderline existential.

Then, upon these foundations are scattered wonderfully specific assertions, gathered from descriptions of classes, spells, monsters, and magic items. High-level fighters can become Barons or Baronesses, implying an established peerage. Neanderthals attack ogres on sight, though we don’t know why. Unguarded treasure always contains silver—not sure about that one, either. Elves are immune to ghoul paralysis. Your guess is as good as mine.

The Power of Suggestion

This is how the implied OSR setting works: The rules describe effects, you determine their causes. The beauty of the implied setting is that you already know the outcomes, but you have complete creative license to explain them.

Why are elves immune to ghoul paralysis? Here are three possible explanations:

• Ghoul paralysis has no impact on Fey creatures, so elves are immune, as are sprites, pixies, nixies, and dryads.
• Ghoul paralysis is a mental reaction to fear, and elves are able to suppress the fear response.
• Elves made an ancient pact with an immortal patron of the undead/underworld/death; immunity to ghoul paralysis is their end of the bargain.

Regardless of which option you choose (or invent), you’ve just converted a game rule into setting lore. In my World of Trid, I created a fourth option—ghouls are undead elves—and this helps me build other parts of the setting. By implication, elven ruins are bound to shelter ghouls, elves may actively search out and destroy ghouls, ghouls probably occupy “bogeyman” status in elven lore, and maybe there’s an elven ritual to put ghouls to rest.

Note that I’m not terribly interested in those detail right now. My goal is more foundational. By assigning a cause to a rule condition, I’ve created lore to engage my players with the setting, all without changing mechanics or inventing anything new that would imbalance play.

Final Thoughts

Ideally, a cover-to-cover read of the B/X rules (all 128 pages) reveals everything the implied setting needs to support, and you can go into as much or as little effort into incorporating them into your world’s lore. Fortunately, you don’t need to create an exhaustive catalogue of these implications—they’re already built into the rules, so they’re essentially “represented” whether you highlight them or not. However, figuring out reasons why these implications exist is a great way to start developing your world hooks or, at least, setting your B/X world apart from any other.

---

If you enjoy worldbuilding tools, templates, tips, and examples, consider joining our Patreon. Membership is free!