The final authority I want to discuss is dice, or random processes in general.
Games succeed when they meet a player's perfect point of challenge - when control and surprise are mixed exactly to his or her liking. Surprise in games can be achieved in three ways:
1. Complex gameplay - enough to present a problem-solving surprise, even when all moves and pieces are completely visible and non-random. This is the approach of classic strategy games, like Go and chess. They manufacture surprise through the players' own emerging insights into game problems whose solutions weren't entirely obvious from the start.
2. Partial information - some things in the game are known to one player but not the others. Rock-paper-scissors carries this out at a very basic level; against a truly random opponent there is no reason to choose one secret outcome over others, and the game becomes sheer random guesswork. Poker is a better game for meaningful guesswork, as von Neumann realized when formulating game theory. The tension in poker is between making the optimal plays given your cards, and giving away their true value to other players through those plays. The potential for surprise is always there.
3. Random procedures - dice, cards, knuckle bones, yarrow sticks, what have you. The cheap and easy way to achieve surprise from time immemorial.
These three paths to surprise actually correspond to three game refereeing modes, if you make the insight of counting the referee as a player.
Following the path of complex gameplay, the referee lets him- or herself become surprised by the interaction of material made up on the fly with the creativity and initiative of the players. These kinds of interactions are deterministic but don't feel that way, because they come out of an unpredictable dialogue about what is possible. There is nothing truly random; what happens is whatever players make happen, vetoed by what the referee will allow, constrained by the limits of plausibility for everyone. This is the improvisational mode.
Following the path of partial information, the referee writes down contingencies beforehand for the consequences of player decisions, works out solutions to deterministic puzzles, and plans detailed encounters with opponents. This is the prepared mode. Player success here is a matter of figuring out, in a way, whether the referee has put the troll behind door 1 and the treasure behind door 2, or the other way around. Whether this game resembles the faux-random game of Rock, Paper, Scissors, or the more subtle guessing game of poker, depends on how adept the referee is at planting subtle clues, and how adept the other players are at finding them.
Following the path of randomness, the referee uses dice, but for two subtly different purposes. One use of dice I'll call the resolution dice mode. This happens when a referee knows the chances of something happening are between "no way" and "sure shot," but lacks something crucial to be able to judge it in a deterministic way. That missing element can be lack of knowledge. Let's take combat. Unless you are one of these guys, I don't think any sane referee would want to judge the blow-by-blow of combat in improvisational or prepared mode. Even if you came up with an answer based on years of sword combat experience, the players wouldn't buy it, and it wouldn't feel fair when they got hurt. There are just too many unpredictable factors in combat for your decisions to sound like anything more reasonable than kids playing "Bang! You're dead."
The missing element that propels referees into dice resolution can also be lack of patience with preparation, or lack of confidence with improvisation in other areas. Instead of going through the whole song and dance with moose heads, statue arms, and hinged busts of Shakespeare, sometimes you just want to roll a 1 and find a secret door.
Even more interesting from my point of view is the oracular dice mode. The twist here is that the referee is not using dice rolls to see how well the players succeed in their actions, but to determine the very makeup of the world around them as they discover it. Monster hit points ... rolled-up player ability scores ... wandering monsters ... and any other random tables for generating content on the fly ... all of these represent the oracular mode.
The oracular use of dice solves a nagging problem with both the improvisational and prepared approaches to setting up challenges for player characters. Often, a deterministic solution will depend on a match between a resource a character has, and a problem he or she encounters. Even if resolved randomly, game flavor demands that there are bonuses to resolution rolls from favorable match-ups, and penalties from unfavorable ones. At this point, the all-important sense of fairness can start to waver. Either the player complains they never meet a two-headed troll to slay with their sword +1, +5 vs. two-headed trolls; or the referee feels obliged to send a conga line of two-headed trolls to be carved into kebab; or there is some middle ground which feels awfully like a carefully plotted out, artifically fair middle ground, and not at all like real life.
The oracular solution, though, feels like real life: it's completely unknown to everyone just how often the character will run into a two-headed troll. And for that the absolute best thing is a random encounter table with a slot for two-headed trolls. (The other satisfactory solution is for the player to take part in improvising the adventure and actively seek out favorable matches, asking in every tavern for the nearest two-headed troll lair; but even this should only increase the chances for a troll roll, not guarantee it every time.)
The reason oracular dice are so interesting is the possibility of using them to settle a number of situations usually sorted out with resolution dice rolls. For an example that got me thinking along this track, take a look at the language rules in version 0.5 of James Raggi's Lamentations of the Flame Princess ruleset. Every time you encounter a new language, you roll to see if you know it, the chances being determined by your Intelligence.
At first glance, this seems crazy; what do you mean I don't know whether or not I speak Finnish until I run into an actual Finn? But when you consider the alternative, it starts to sound crazy like a fox. The alternative is the two-headed troll problem. As the preparing referee I have to decide what language the all-powerful army speaks; you know, that army that can only be dealt with by parleying. I know what languages all the player characters speak. So do I screw them or give them a break? Why not just roll for it? That way, any outcome seems fair; blame it on the dice, you had your chances.
(As an aside, though, my preferred solution would have the roll be for what language the army speaks, and see if it matches the characters' known languages. Not knowing which languages you speak, for instance, deprives you of the ability to choose to travel to those areas or seek out those people.And then there's the munchkin factor, where players try to speak to as many people and read as many old manuscripts as they can to max out their language skills ...)
Here's another infamous example familiar to most of us. A certain game gives a character with a Super Duper strength a 50% to bend bars and a character with an Average strength only a 2% chance. Furthermore, this game allows only one try per character to bend bars, for fairly obvious reasons. So Super Duper Man blows his roll and Average Guy makes it. That doesn't make sense. Why not have the roll be oracular: determining the strength of the bars? That way both characters can bend weak bars (roll of 02) but only the muscleman can bend strong ones (roll of 47). Strength of bars, hiddenness of secret doors, complexity of trap mechanisms, and other "skill roll" problems could all benefit from taking a closer look at the oracular dice possibility.
Now, although this is a good wrapping up point, I'll just point out that all the above comments about referee decisions also hold true for rules. Because, as I explained last time, game rules are just referee decisions written down and standardized. This is true whether the rule tells you it always happens, it can't happen, or you have to roll for it.
Researcher in social science and appreciator of hexy wargames, role playing games, interactive fiction, board games, and CCGs. I've learned a lot doing design and rules editing work on the side for the Legend of the Five Rings CCG. But this blog is mostly about other things.