Box and Bones

Box & Bones is a design pattern for role-playing games. Its principle use is as a procedure for building a setting or situation by randomizing the selection of prompts. It is similar, in that regard, to the use of “spark tables,” though the procedure lends itself to greater specificity and opens the way to some interesting variations. Because it can be used compensate for the absence of a setting master, Box & Bones is particularly useful for designing solo games or scenarios.

Basic method

At its simplest, the Box & Bones pattern requires:

When a prompt is needed (e.g. when a character travels from one location to another), the player uses the method to select one. This is done by:

  1. Rolling the dice;
  2. Consulting the tables to find the descriptors corresponding to the first two results;
  3. Cross-referencing the two terms to find the corresponding list of prompts;
  4. Using the third result to select the matching prompt from the list.

The resulting prompt then forms the basis for elaborating on the scene through play.

On its own, Box & Bones provides no procedures for developing a scene beyond its prompt. It must be paired with other rules or design patterns to facilitate the rest of play.

An example

In Follow the Bones, the Cairn adventure that originated the method, the character sets out to find the cairn at the heart of the Woods. Each time they travel through the setting, the player consults the bones by rolling three d4s. Suppose the first roll yields a result of 2–1–2. The first 2 corresponds to “Grim” on the Circumstance table, and the 1 corresponds to “Atmosphere” on the Feature table. Consulting the “Grim Atmosphere” list in the scene prompts and counting down 2 spaces (the value of the third die), they arrive at the prompt: “Ash and cinder drift along the breeze.” This furnishes the key details on which the first scene will be built.

Expanding on the method

By randomizing the key elements of each scene, the method preserves the experience of discovery. Since no one is responsible for deciding what specific elements will come into play, the player is free to be surprised by the results. The tables corresponding to the first two dice establish broad themes that help shape the players interpretation of the scene. The third dice furnishes details, narrowing the range of possibilities down to a specific prompt. This basic model is flexible, and can be adjusted to produce a wide range of effects.

Working with prompts rather than “sparks” gives the designer more precise tools for shaping the potential character of a setting. Players accustomed to the greater creative latitude afforded by spark tables may find that limiting. In fact, omitting the third die leaves you with exactly the sort of abstract, two-word prompt you’d get from a spark table. In this way, the system can be said to collapse gracefully.

Using all three dice affords greater dimensionality. The results of rolling the “bones” can be conceptualized as picking out coordinates in a 3-dimensional space; this is the “box” named by the method. So, for example, we could visualize a roll of 3–4–1 as plotting the course illustrated in Figure 1.

"Box model diagram"

This can be complicated by providing multiple boxes, each determining a different aspect of a scene. Follow the Bones, for example, has players consult the bones to determine both Scene and Encounter.

Ordering keywords or prompts according to some value (say, from more dangerous to less dangerous) allows you to use dice modifiers to push results around the box. So, for example, a +1 modifier would allow the player to push the 3–4–1 result to 3–4–2 instead. What Fiend Stalks the Night uses another design pattern, Riddle & Tilt, to push results around the box.

Designing for Box & Bones

It sometimes helps to work backwards, writing out an initial set of prompts and deciding based on those what size dice to use and which keywords work best for your tables.

Any size dice will work, but the larger the dimension, the more prompts you’ll need. At a minimum, you’ll need as many as the value of dice1dice2dice3. If you design for three d4s, then, you’ll need to write at least 64 prompts. That’s easily enough variation for some scenarios. Designing for three d20s would require 8,000 prompts!

The bones need not be all the same dimensions. You could specify, for example, d4s for the first two dice and a d6 for the third. At least in the basic model, the important thing is that the dice have a consistent order.


Box and Bones is a design pattern describing a set of procedures for play—what are sometimes called "mechanics." As far as I know, game mechanics are not considered intellectual property under US law, so there should be no legal barrier to their use. This page is published under a CC-BY 4.0 license. You're free to use the text and images here so long as you provide appropriate credit and indicate what changes, if any, you've made.

The following logos are provided so that you can mark games that utilize this design pattern. They’re free to use, but not required.