What this Article is, in Fact, About

The most unique parts of the Longship game design are the dynamic weather system mechanics and the CargoMaster mechanics. By freak happenstance, these also happen to be the most enjoyable parts (according to playtester reviews, not just my random opining). But this Gamasutra feature isn't about either of those. Why? Because, that's why.

Instead, this feature is about the dice-based mechanics in Longship, which make up a small but important part of the game. See, I recently retooled Longship to use custom dice instead of straight d6s, so I thought I'd explain some of the design decisions and math behind the new mechanics that are associated with the dice. Like I stated up front, I really want to show some applied probability theory to prove that it is useful in more situations than just bombastic talks at the Cigars and Brandy Club for Designers.

In some past versions of Longship, it used many more dice, but currently the game uses only two six-sided dice. Crude or sloppy dice mechanics are a hallmark of AMERITRASH design, so once the rest of the game was working fairly well, I decided to take another pass on the dice-related mechanics and give them more polish and personality.

Although I toyed with the idea of removing dice altogether, they have an important role to play in the game. First of all, randomization to some degree can be a very good thing. Some games are superb without it (Chess, Go) but games for a family setting and range of skill levels benefit from some chance. We've seen this in the American classics Monopoly and Risk, but randomness plays an important role in Eurostyle games as well (which I love). Settlers has the all-important (and sometimes detested) 2d6, Carcassonne has the random tile-flipping, Ticket to Ride has card draws and route draws, and so on.

The Not So Grand Game of Goose

_{The Game of Goose}

The degree of randomness is often what throws games firmly into one design camp or another (Ameritrash or Eurostyle). Subject for another article, but long story short is that too much randomness destroys the meaning of choice in the game, and that's a bad, bad thing for most designers and players alike. While the "GRAND GAME OF GOOSE" was interesting in its day, games like that are just not up to snuff two centuries later. Chutes and Ladders does have its places, I suppose.

Two Dice, How Do We Love Thee? 36 Ways, Says I...

2d6 (or two six-sided dice) based mechanics are familiar, flexible, tunable, and all sorts of super things. They are great game tools.

_{The World Famous 2d6}

Familiar: people are used to rolling two six-side dice and don't find it strange at all. Thank Monopoly. Other polyhedrons have an RPG-inspired stigma.

Flexible and Tunable: with 2d6, you can achieve a lot of different number distributions and mechanics. You can use each dice individually, combine them together to get numbers (e.g. Craps), or use one die as tens and the other as ones. If combining them, which is of course quite common, then the probability spread of the numbers 2 though 12 gives you a lot of flexibility to work with. There are 36 different combinations of the dice, so you can make events as rare as 1/36 (2.8%) or as common as you want (by allowing spreads of numbers... e.g. "You succeed on a 3 or above on two dice (97.2%)."

For Longship, though, I wanted something a little more special. Design-wise, there are times when other dice (d4, d8, d10, whatever) are needed to achieve whatever probability or mechanic you are aiming for. When choosing other dice, though, you run the risk of alienating players and/or attaching a strong stigma to the game. Sometimes anything other than a d6 screams D&D to people, which can be bad. Poor polyhedrons, always getting a bad rap.

Before you scream "Stop talking about dice, I'm a digital designer, curse you!", remember that you face a similar crisis of familiarity when coding events related to a random number generator. Sure, you can use percentage-based systems or get as complex as you want in the code, but where user interface is involved, you must still consider familiarity issues. I personally love percentage based systems, but we still see tons of video games with d6ish, d8ish, or d20ish mechanics, and that's partially why.

Returning to our heroic yarn, I wanted a good randomizer with the flexibility of 2d6 but I didn't want to go with a tile deck or card draw or a spinner or some other mechanism that basically screams "I'm dice but I look so much more sophisticated, don't I?" In truth, I needed what 2d6 had to offer but wanted to add a little more theme and interest. Enter custom d6s. After a bit of work, I settled on the following: