Truly Random - A Practical Example

Recently I was watching an episode of Table Top on the Geek and Sundry website. The game was “Tsuro of the Seas”. (

In this game, on each turn you have to roll 2d6 to determine if you’ve awakened the dragons. If you have, then you roll a single d6 to determine in which direction they move.

Let’s look at how we might implement this with Truly Random.


Roll 2d6. If 6, 7, or 8 are rolled, the dragons are awakened.
If awakened, then roll 1d6 to determine the dragon’s movement.

There are a number of ways to implement this in Truly Random.

  1. We could simply use the RPG feature and roll 2d6 followed by 1d6 if necessary.
  2. We could develop an RPG+ group where both sets of dice are rolled and you just determine whether or not to use the movement roll based on the 2d6 roll.
  3. We can develop a Custom Dice Set that handles it all.

We’re going for option 3. This seems like a lot more fun.

We know there are 36 possible combinations you can roll with 2d6. Since we are interested in rolls of 6, 7, or 8, we need to know how often they occur in this distribution.

2d6 = 6: 5 times
2d6 = 7: 6 times
2d6 = 8: 5 times

So, 16 of the total of 36 combinations will result in a dragon movement. A little math to simplify this: 16/36 = 4/9.

I’m going to implement this using a single custom die. This die will have two faces:

  1. The Dragons are not disturbed.
  2. The Dragons have awakened and move 1d6.

Since the first face can occur 5 times in our example (5/9), I will give it a weight of 5. Likewise, I’ll give the second face a weight of 4 (4/9). In this way the two faces will now match the statistical distribution envisioned by the game designer.

It really is that simple. This is the xml you can import into Truly Random for this game. I added a little formatting to “awakened” to help catch your attention.

<?xml version="1.0" encoding="utf-8"?>
        <title>Tsuro of the Seas</title>
            <title>Awaken the Dragons</title>
                <title>The Dragons are not disturbed.</title>
                <title>The Dragons have &lt;b&gt;awakened&lt;/b&gt; and move %%</title>