Warning: Dry Designer-ey blog post ahead.

Many people look at chance in multiplayer games as a bad thing. That the player with the better skill should always win, no matter what. That a game of, say, Street Fighter should be determined when both players walk up to the machine, not as the play progresses.

So what role, then, can chance play in gaming? First, a little background (Note, because this is a quickly written blog post there aren't as many hard facts as there should be. Google if you want to be convinced.)

Human beings are eternal optimists. We all know that we statistically cannot win, yet over 2.5 billion dollars worth of lottery cards are sold annually in California alone. The Vegas airports are full of slot machines (even though mathematically you will lose), and online poker has grown to the largest form of online gaming.

Why is this? As an oversimplification, humans always overestimate chances when there is randomness involved. We chalk this up to fate, the will of god, or just plain lady luck. In other words, there is super situational value attached to luck.

So how to we yolk that to making people want to play a game? How do we make a game of randomness with actual play?

Let's take a simple dice game for an example. Call it "guess total number." Two players simultaneously roll three dice each in a cup. Each player looks under their cup, then guess the total number on all dice under both cups. They go back and forth guessing progressively higher numbers. At some point, one player will challenge the other player's number at which point, the guessing stops. If the challenged player is below the total, they win. If they're above, the other player wins.

Now, if you play this game once, it's pretty random. You don't know the numbers, and you don't know your opponent. Play it 10 times, however, and you learn how your opponent guesses. You see how their initial guess and their subsequent guessing patterns gives away what they know about their dice.

But while there is actual gameplay going on above, even a beginner has a chance of winning. No one person can win all of the time. The illusion of a chance of winning is a powerful motivator.

But you still want competition to be fair. And for that, you need to carefully monitor your accuracy and your precision.

Precision is the ability to, for example, take a dart and put it in exactly the same place every time. However, it doesn't actually mean that the dart is going where you want it to. If you're a very precise thrower, you may throw 100 darts, and 99 of them wind up on the double 3. You could be aiming for the bull's-eye, but you always hit in the same spot... just not where you're aiming.

Accuracy is the ability to, ON AVERAGE, put darts where you want them. This doesn't mean any of them actually hit the spot you're aiming for, but that if you averaged all the positions, you'd get to that spot. If you threw 100 darts at the bull's-eye, and they all splayed across the board... none of them may have actually hit the center, but if that's where they average out to, then that's a technically accurate series of throws.

With randomness in a game, you want high accuracy and low to medium precision... I.E. a stronger player will win more often, but a weak player always has a chance.

Another way to temper randomness without nerfing the illusion of chance is to repeatedly roll the dice. A super simple game might have 2 players rolling one die each, and the player with the higher die wins. That's totally random. Now, let's simulate one player being better than the other by always having player 1 win any tie. They're not tremendously better than the other player, but they do have a little more ability... roughly 16%

So after 1 roll, player 1 has a 58% chance of winning. During a best-of-3, that goes up to 63%. During best of 5, that goes up to 70%. If you roll a full 21 times, (which should take all of 1 minute of dice rolling) the better player has a 77% chance of winning. Thanks to repeated chance encounters, that initial 16% difference gets magnified to a 77 to 23% gap overall... The weaker player always has a chance of winning any given encounter, and probably has the illusion of winning the overall game, but the slightly more skilled player will actually win the war almost 4 times out of 5.

Like chainsaw battles in Gears of War, randomness can be a cheap route to fun. Just don't blow the balance between accuracy over time and precision, and your game could be the next Diablo.