I have been beavering away on Reel Adventures of late, trying to get the game working precisely the way I want it to. One of the recent changes has been to take the dice out of the resolution system and use cards instead, which got me thinking about the sort of deciscions that would lead you to choose dice or cards for your system.

Why use randomisers at all?
First things first, why should you include a randomiser in your game? If you think about it there are plenty of successful games, chess coming instantly to mind, that have no randomiser in their system at all. On the other hand there are games that are only randomiser, snakes & ladders.

The main reason to use one is to make the outcome of a given choice uncertain. This can increase tension and excitement in the game and force players to react to an ever changing set of circumstances. For example in most wargames the way of determining whether my guy kills your guy is to roll some dice based on, or compared against, unit stats. If it was just a straight comparison the game could become very dull and all about the superior troop type, meaning all players would just field the strongest force they could. The introduction of a random element means the choice of army is not 'obvious' and you get a more diverse spread of troop choice which can only make the game a bit more interesting.

However the introduction of randomisers must be handled carefully. Snakes & ladders, though an entertaining game when you are a child, is actually terrible from the point of view of design. Their is no choice for the player and all you do is roll a dice several times until someone wins. The game is all randomiser and no choice. This is to be avoided at all costs.

Randomisers in RPGs
Now RPGs, and especially story focused games, introduce another factor worth considering. The choice we have mentioned above becomes more interesting as the players, I include the GM here, are creating a narrative that other players can react to. In a way the other players introduce the random element we can get from cards or dice and as such the need for a randomiser to create unexpected situations is lessened.

That is not to say we can always design RPGs without a random element, and indeed most still include some kind of dice or card mechanic to decide the outcome of combat/ social situations etc. Those without these randomisers must be careful to not fall into the trap of making all deciscions fall to one player, GM fiat for example, or to reduce it to such a point that it is non-existent and the game has no suprises for anyone. For me the thing that makes RPGs so interesting is the unexpected twists and turns in the story that we create.

Once you have decided to include a random element in your design, you need to decide which one.

Dice
Games have been using Dice since, almost literally, the dawn of time. The most common dice is of course the d6 and is readily available, in small quantities, in most households. Now our hobby has more dice than I can really mention and you could write infinite words on proababilities, why a d6 is better than a d10 etc. I am not going to do that here.

What I will do is lay out why you might want to choose dice over cards.

1) Probabilities: Ok I am going to mention it briefly. The core range of polyhedrals offer and interesting range of probabilities, some of which may suit the mechanic you are thinking of better than a deck of cards will. The core range is: d4, d6, d8, d10, d12 and d20.

2) Visually: They are an instant number you can read easily and as long as you don't have too many fancy calculations in your system resolution is instant.

3) Familiarity: It is more common to use dice in a board game as the randomiser than cards and as such people are more used to seeing them used in a gaming context.

4) Addition: If you are pooling and adding them together then they are easy to add as the numbers are instantly there. You don't need to think about how much a face card is worth.

5) Quantity: You can roll loads of dice easily in your hand but holding more than 10 cards say is a bit troublesome. However not everyone has loads of dice so there can be an accesibility issue there.

Cards
I have been heading towards using cards in my game design since 'Mob Justice', basically because I think you can play more interesting narrative tricks with them. However they aren't all good and carry their own set of problems. So why would you use them over dice:

1) Accesibility: Every household, pretty much, has a deck of cards in it and is familiar with the suits and value. You show the average joe a d12 and he will look at you like you just insulted his mother.

2) Visually: They are bigger and impact more on the play area than dice. This can be good, from the point of view of everyone being able to see it, and bad, means you need more table space.

3) Quantity: Holding more than 10 cards in your hand can be a bit cumbersome, though is not impossible.

4) Probabilities: A lot trickier to calculate with cards and something that you really need to think about when designing a game. Does every player need a deck? Do the proabilities balance out as players draw cards?

5) Addition: this can be harder than with dice if you are including face cards as people need to think about what they are worth. However it means you can play tricks with their value that can be useful.

6) Tricks: You can play tricks with leaving cards on the table, bluffing, winning whist style tricks etc. that you can't with dice. This gives us more design opportunities to maniuplate player behaviour, but that is another post, or 10, all in itself.

So there you go. Dice vs. Cards is something that will be debated for a long time yet and either method has its pluses and minuses. I will post more soon about exactly why I chose cards over dice for Reel Adventures.

All the best

Iain