I was fortunate to attend PAX East a week or so ago. I had a great time, and got to meet and listen to some of the smartest people in gaming. And you know what a lot of those smart people were talking about? Choices. In computer games. So, I will also talk about choice in computer games, and that will make me look smart too. S-M-R-T.
Now, there are plenty of games out there where user choice directs the way the game goes: The Sims, Dwarf Fortress, Spore... sandbox games that don’t have much of a designer-driven narrative. Now, both of those games can have pretty vivid player-driven narratives, but those are unreliable, and not at all guaranteed. Besides, the random number generator can be a lousy storyteller: sometimes you look up at the sky and the clouds just look like clouds.
Many games that are considered to have told strong stories have been very rigid, railroading the player from one plot element to the next, often showing off a series of pre-generated events. The result is a cohesive story that everyone who plays the game can play through, see more or less the whole thing, and then compare notes at the coffee machine. Now, not all linear games are purely linear: like extras on the DVDs, it’s been common to make it possible to get elaborations on the main story by doing additional tasks -- Final Fantasy VI was great for this, with some deeply hidden bits of characterization, and even a willingness to leave story elements unresolved if the player didn’t bother looking for a character in the second half of the game.
But... linear storytelling is such a crazy rigid thing for such a mutable medium. Historically, stories have been changeable: campfire stories, fairy tales, epic poems -- all these things were traditionally tailored to the audiences, which is why Beowulf and the Iliad were so full of carefully dropped names. Everyone likes different things in a story, and when you’re writing a book you can be as narrow as you want, targeting your vegan amputee bulimic skier demographic with laser-like precision. Because hey, with your artistic purity and a case of ramen, you can at least live long enough to get pellagra. But games can cost serious money to develop, and it is frequently desirable to have a multi-digit audience. The larger the budget, the broader the appeal needs to be. You can either achieve that by making the story as bland as possible, filled with violence and T&A, or you can embed many different potential narratives into one game, customizing the game to the personality and interests of the player.
There have been a number of different approaches to that. One example is basically the switched-track railroad: the designers embed multiple plots into one game, and you basically pick the plot you’re watching by throwing switches. These limited, discrete choices can make for very different games, or (more often) basically one story with a bunch of different endings, but are time-consuming to write. As a result, there have tended to be fewer paths, such that a given player can revert back to a few strategic save points and see all of the endings, a practice known as completionism. Sometimes these folks are derided as playing a game to death, but it seems to me that usually they are cherished: they’re rewarded with super-difficult endings that are unlikely to arise through ordinary gameplay, and are often directly marketed to on the box. (“Over 15 nearly identical endings!”)
A lot of the different approaches come from the tabletop gaming realm, and the kind of game you play doesn’t depend entirely on the plot(s). The first big one is character customization: you spend a lot of time with the PC, and getting to customize a bit can help a lot. Even just picking a party of stock characters, some players will give those characters strong personalities. Quest for Glory did this particularly well, I thought, offering multiple paths through the game for the initial three basic character classes.  Sometimes all it takes to make a story more interesting to someone is to better match the player... but the big pitfall here is that this little bit of generosity might say a little too much about who you think your audience is (or rather isn’t).
Part of selecting the protagonist can also be modifying abilities, usually derived from the Dungeons and Dragons group: Strength, Dexterity, Constitution, Wisdom, Intelligence, and Charisma. (Sometimes also Luck) By choosing a character with, say, high Dex/Int and low Str/Con (See? I speak the lingo!) you have to solve problems very differently than the other way around, leading to a different type of game. Or failure. And if you screw up or just find your play style changing, there are usually ways to alter those stats (and thereby the nature of the character) during gameplay, by spending time leveling up or looking for special items.
Now, that’s basically just selecting the protagonist, but a number of games (and those of Peter Molynieux come to mind first) customize that protagonist at a purportedly deeper level over the course of the game according to the choices that the player makes, usually to place the character on an axis between two extremes. The simplest, and to my mind most common axis is good vs. evil. Do a good thing, you get nudged in the ‘Good’ direction. Do a bad thing, you get nudged in the ‘Evil’ direction. The trouble is, these games usually betray a somewhat simplistic conception of evil, and frequently are very bad at looking at the big picture. Also, possibly because some game designers are apparently uncomfortable with players being ‘evil’ just because they’re bastards, it seems sometimes that they go out of their way to make it so that the choice is more a practical matter between ‘good’ and ‘convenient’ or more generally “Do you use your powers for good or for awesome?” with only the notion of ’this is wrong and no-one should do it ever!’ to prevent the more objectively useful option ... which is itself an interesting statement about the source of morality, but in practice I usually find it pretty lame, especially in games where as the protagonist you had to hack/slash/shoot your way through a bunch of one-dimensional enemies just to get to that moral choice. Killing a whole lot of people and taking their stuff is overlooked, but lying or cheating at cards will get you shunned? That’s... pretty historically accurate, actually. Moving on.
The basis behind these sort of choices is the notion that there is no right answer, that there’s always a tradeoff. This can work much better in games where the choice isn’t between good and bad, per se, but about how the player views the character. Arcanum is my favorite example of this. In that (fantasy steampunk RPG) game, the choices are generally between technology and magic: consistently favoring, say, technology, rewards the player for a sort of purity of vision with awesome things like steampunk robots, but allows the door to magic use to be slammed firmly shut. At any given point, it might be advantageous to go against type, but it would run counter to long-term goals and the vision of the character. I was fortunate to attend a talk given by the fine folks at Oblivion about choice in their upcoming game Alpha Protocol, and one thing that they mentioned (let slip?) is that while all the choices can stand alone, they were designed around a handful of familiar archetypes (the suave James Bond type, the intense Jack Bauer type, or the pragmatic Jason Bourne type. (Huh. Check out those initials.)) and I suspect that the plot of the game will show a bit more thematic consistency if the player sticks to one of those types.
Then there are the approaches that basically ask the player up front what kind of game they want, or code it: picking one’s favorite color in Moonmist, for example, or that tarot reading at the start of Ogre Battle. I’m not sure I’ve seen that done well, honestly.
There is another tactic that’s being used increasingly, of giving the computer a more deliberate role of gamemaster, with the tools to gauge how the game is being played and adjust accordingly. The ‘director’ in Left 4 Dead is a good example of this: it can tell generally whether the players are being cautious or reckless, for example, and throw different kinds of zombies at them to make the game more challenging, or potentially adjust the difficulty to a team that’s doing particularly poorly or very well.
So, what’s to be done? Where’s this going?
The funny thing is, games are already all about choices and style. In a first-person shooter, does this player do a lot of exploring, or get straight to the point? Does this player kill everything that moves, or spare fleeing enemies? In an RPG, does this player walk around in mis-matched armor with a weapon at the ready, even in town? Does this player totally blow off the main plot in favor of looking for treasure or searching out weaker enemies to kill just for the experience of having done so?  In an IF game, is the player a total kleptomaniac, picking up anything at all regardless of obvious consequence, or are objects only picked up when there is an obvious use for them?  Games frequently offer optional ways to be in-character, like closing doors or turning off lights when leaving a room, or otherwise cleaning up after oneself (I’ll refrain here from overtly spoiling the Last Lousy Point in a very good game by Admiral Jota).
I’m going to go out on a limb here: I think that there is little point in setting up deliberate, discrete choices if the game ignores all the common choices already being made by the player about how to play the game. And I think I see a trend in games to include those choices more actively in the narrative. Now, am I eventually going to be playing a game that basically embeds an MBTI-style personality test to determine just what story I’ll personally find the most satisfying? That would not surprise me. But it would, I think, likely be a disappointment. I think that the next game that really wows people is going to be a bit of a cross between Left 4 Dead and Fallout 3: a sandbox-type game with a range of morally ambiguous paths with multiple axes of personality traits emerging (not just good vs. evil, but pacifist vs. violent, talkative vs. quiet, packrat vs. traveling light, etc) , and a ‘director’ that analyzes style of play and adjusts the plot accordingly. Such a game could do that without ever presenting the player with an explicit choice. (Also, five bucks says that the protagonist in the first such game to do this well is mute, like Chrono)
Anyway, I’ve been sitting on this post and tinkering for the better part of a week. Time to cut the beast loose and let you all kill it.
 OK, rant time. I played through those games when I was a kid, and managed to turn a rogue character of mine into a paladin in the second game, without hints or anything. I kept that character through the fourth game, and then held onto that file on a floppy disk for freaking YEARS waiting for QfG 5 to come out. When it finally did and I finally got a copy, I found a floppy drive, went through those old disks, and found them all succumbed to bit-rot. I was So. Pissed. Off. I almost didn’t play QfG 5 as a result.
 I’ve made the point before, but it’s worth repeating: The practice of ‘grinding’ is an inherently evil, vicious act. Imagine hearing a third-party report of a typical ten minutes spent grinding: “Yeah, this guy decided he needed killing practice or money or something, so he went out where he knew he’d be attacked, easily finished off the poor bastards he came across (even when he surprised them!) then collected their belongings and sold them in town.” Even killing horrible monsters is morally ambiguous if the player knows that there is an unending supply, particularly if the plot involves finding another way to “clear the land of taint”. That doesn’t mean that a game cannot or should not have these elements, only that they should be treated with a bit more... sophistication?
 I do *not* mean the frequently-obnoxious tactic of preventing the player from picking something up before it’s ‘ripe’, or the practice of making every object either mobile and useful or non-mobile and not useful. Nor am I talking about games (*cough* Hitchhiker’s Guide *cough*) that punish the player for not having grabbed something non-obvious earlier. I’m purely talking about reasonable self-restraint here.