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Designing with Frontiers

Frontiers is a set of rules you can use, and also a set of rules with its reasoning written down, so that using it teaches you something about designing systems of your own.

That is the job this documentation does. Seven documents, one per subsystem, each built the same way: here is a problem every tabletop game has to solve, here is how other designers have solved it, here is what Frontiers does, and here is which parts of that you can change without breaking anything.

It informs, it does not instruct

None of it tells you the right answer. Where the engine leaves a choice open, the text names the recommended option and the alternatives worth weighing, so that any change you make is one you meant to make.

You can read these documents having never played Frontiers and never intending to. The problems are the same whichever engine you build on.

Read a Ruleset first

These assume you know how a check resolves. Start with the d18 Ruleset, or see Rulesets for all three.

   

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The seven documents

Read them in order the first time. Each leans on the one before it, and together they walk from a single die roll out to a whole character.

 

The Resolution System Start here Targets, the roll, and the Gradient that says how far past the line you landed. Everything else in the engine eventually resolves through here.

Flow of Play Time and tempo Actions, Activities, Encounters, and the shape of a session. How a game decides when time matters and when it does not.

Attributes & Derivatives The foundation The four Attributes, what they feed, and the difference between a value that recalculates and one that is written down once.

Skills Trained capability Why Frontiers makes Skills binary, why they grant Favor instead of numbers, and how to build a list that fits your genre.

Abilities The ϟ Energy economy Card anatomy, the Demand and Capacity rule, and the problem nobody has solved cleanly: balancing what a character gets for free.

Equipment Gear and carry The four item states, Slots, held ϟ Energy drain, and why all item handling collapses into one Free Action.

Characters Building and growing Origin and Archetype, the order you build in, and the two-track advancement split between Marks and Levels.

   

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How to use them

Read the subsystem you intend to change before you change it. Most design mistakes come from moving a load-bearing decision without noticing it was one.

Each document closes by separating two kinds of change:

Variants

Numbers and thresholds you can turn freely. Tuning. The engine behaves the same afterwards, just harder or softer.

Alternatives

Changes that alter what the engine is. Replacing binary Skills with graded ones, or Favor with flat modifiers, is allowed and sometimes the right call, though it does leave you building a different game, which is worth knowing going in.

 

Every system referenced across this documentation is collected on the 1.0 release page, with links.