In the first part, I talked about was that the designers of games could cleverly craft their worlds so as to subtly (or sometimes not so subtly) guide players along the intended path.
Now I'd like to talk about way #2: Attempting to change the game world in reaction to the user's behavior.
This is almost never done. Games almost never do it. For the most part, game environments are designed as either static, unchangeable things, or in some cases (roguelikes, in particular) as randomly generated levels that are different every time, but consequently, usually fairly bereft of intentionally crafted puzzles or challenges.
Now, I have nothing against roguelikes. (Some of my best friends are roguelikes!) And the model of the world being fixed makes a lot of sense from engineering, asset-management, and scenario planning angles. The fixed world is nice because you get to draw maps, (which is fun) and means that players can talk to each other meaningfully about where they are in the game. It also means that you know in advance what spatial relationships exist between interesting things, and can manipulate them as needed. (Especially when it's useful to force the player to go through something before seeing something else.)
What I've gradually become convinced of is that neither fixed worlds, nor completely random maps are the final solution. Looking for a moment the pencil-and-paper role playing scene, it is telling that all of the conventional wisdom points GMs away from fixed worlds, or random worlds. (Which I guess are also fixed worlds, but from a different source.) In tabletop gaming, when stories work, it is frequently because the GM carefully adjusted the world, and the order of events, in such a way as to make a better story. The more that is fixed in advance, the less the GM can move around later to make a better story.
This works because good GMs know the same secret that stage magicians do: If you don't tell them what the trick is in advance, then you can change the trick as you go to whatever seems most appropriate. In stage magic, this is usually called a "magician's choice", or equivocation. In tabletop RPGs, it is usually called "good GMing".
In tabletop gaming, this sort of approach tends to lead to highly memorable storytelling and situations. So why can't the same thing be done in computer games? Obviously, the computer won't be able to approach the finesse or creativity of a good GM. But there is no reason that I can think of that a game couldn't adjust the world to make it more fun for the player.
The only places I can think of where I have seen this sort of thing done is in the Mars segment of Adam Cadre's Photopia, and maybe some weird, experimental stuff like Warning Forever.
Consider – When the player sits down, they know nothing about the world you're giving them to explore. If they explore east, and find a shrine where they learn how to double-jump, and then explore west, where they find some caves that require double-jumping to progress, they're likely to say “wow, that was lucky, good thing I went east first!”
But what is to stop the game from putting the shrine what ever place they go first? And the caves wherever they go second? The player doesn't know the map, except for whatever minuscule portions of it they have seen first hand. They don't know what is supposed to be where. Maybe some other player went south first. And found a shrine where they learned to double jump. And went north second, and found some caves where they had to double-jump to progress. Players are used to assuming the world is a fixed entity, but is there any reason that we as designers have to follow that rule?
What if the game, rather than operating on a fixed map, was instead set up as a series of things the PC was supposed to experience? Which the game would put on the map in order, as the player explored areas they hadn't seen yet? It would be sort of a quantum map. Any place the player had explored would be “locked down”. If they went there later, it would always be the same. But any place they hadn't explored yet was undefined until they went there, and the game would fill up the undefined spaces with whatever it felt like the player should see next.
The participants in Project Horseshoe this year described the player's experience as a “watery pachinko machine of doom”, but they seem to be approaching it from the point of view of predicting where the ball will land and how to design configurations to get the ball where it is supposed to go. My thinking is rather – It's a pachinko machine, so the ball is going to bounce off of things as it falls, but there is no reason we can't change the positions of the pegs as it is falling.
This kind of design would give us some fairly powerful tools to craft the flow of the user experience. Suppose that somewhere in the game, there was a boomerang. And there was also a boss, for which defeating it required the boomerang. If the locations of both of these things are fixed, then there exists a chance that the player will try to go to the boss before they have the boomerang, and then either be turned away, or fail. If the locations were mutable though, the programmers could know in advance that the player would have gotten the boomerang before they fight the boss, for the simple reason that the boss and his area won't even show up until the player finds the boomerang.
This could work the other way, too. Say the designer has some neat puzzle in mind, where the player is supposed to see the puzzle, and later find a key, and then remember to go back to where they found the puzzle. Say for some reason the designer wants to make sure that the player finds the puzzle first, before the key. This would give them a way of insuring that, and making sure the user experienced it as designed, rather than stumbling on the key, finding the puzzle later, and going “that was easy, I had the key laying around and it just went right in.”
Usually when games want to deal with things like this, they do it by blocking off parts of the map, often in arbitrary-seeming ways. (“Sorry, you can't leave town yet, the bridge is still under construction.”) This would give the player (apparent) freedom to wander wherever they wanted, and have no need to box them in because they didn't have an item required for the lands beyond.
There are dangers, of course. Player knowledge is the biggest one. If they knew that the game would always give them the “temple of the boomerang” on the 5th unexplored screen they went to, then it sort of destroys the illusion of exploring a world. Also, if they know how it is working, (or are just perverse) they can cause problems by various behavior patterns. For example, what would stop a player from running around and “Defining” the whole map, first thing? You might be able to work out some limitations, but ultimately, it would require some careful design on the part of the programmer to make sure the player didn't “fix” too many locations by looking at them, and thus restrict the game's abilities to place things in unexplored space by reducing the amount of unexplored space left.
Also, it there would have to be SOME limitations or the players could define an infinitely large world by just exploring indefinitely. Due to the constructed nature of it, save-game storage space would probably have to scale linearly, so this would not be especially desirable.
Finally, it would probably limit replay value, since, much like a magic trick repeated too many times, on a replay, the player would realize how it all worked, and it would become less of an exploration, and more about just trudging along until the game decided to trigger the next event. It would remove the illusion that the player could affect the game's pacing. The same logic that makes sure they can't go too far without getting what they are looking for would also make it hard to get it early.
I think a game set up like this could work. And would be an experience unlike anything else out there right now. But a lot of work needs to be done before then, and a lot of problems need to be solved and thought through. But still. Who says the world has to exist before you look at it?
Friday, January 18, 2008
Linear vs. Freedom Part II: Mutable World
Linear vs Freedom, Part I: Invisible Rails
Playing Aquaria lately has got me thinking more about player exploration, how fun it is, and how tricky it is to get right without sacrificing other game aspects to. Read on for some random game design musings on walking the balance between making sure the player doesn't get stuck, and letting them feel like they have complete freedom to explore.
It's always been a hard problem. How do you make the player feel like they can go anywhere they want and explore, without worrying that they'll go
somewhere they can't do anything yet, and become frustrated? If you make a giant world with multiple ways to go, there is no way you can ensure the
player will go the way you want or expect. Some of them will go some random other ways, possibly towards obstacles they can't overcome yet.
The usual complaints that this brings out in a user are:
These are things feelings that we, as game designers, usually want to avoid or minimize. Logically, it seems like there are two general classes of solution:
So first let's talk about #1. Trying to modify the user's reaction. This is by far the most common approach taken, and there are several ways to approach it. Most involve attacking these common complaints directly. Here are some solutions I've seen games use:
All of these methods are largely examples of the subtle nuance that is the level-designer's art. They all revolve around crafting the world in a way that guides the player toward the areas that the player is expected to experience next. I like to think of this as the "invisible rails" game model. Granted, in some cases, the rails are built out of game rules (lack of keys or items) and in other cases, the rails are built out of player ignorance (not knowing where to go or what to do) but in all of these cases, the general goal is to make the game world in such a way that the user feels completely free, but is blocked or discouraged if they try to deviate too far from the planned experience.
These approaches have served games well so far, but as the fine people who partake in Project Horseshoe have been telling us, the best stories in games are often the ones that the player feels like they have a play a large part in creating themselves.
This post is already getting pretty long, so I think I'll break it up into separate posts. In part 2, I'll talk about the second, seldom used approach of modifying the game to adapt to the user.
Saturday, December 22, 2007
Tetris... with TIME
I've been trying to figure out why the skill training in Eve-Online works. Not works in a general technical sense. That part is pretty trivial. But works as a game mechanic. That part is harder to pin down. Longish post. Read more below the fold.
On the surface, it actually looks not too far from the inestimable Progress Quest. You select the skill you want to learn. Say, “Missile Launchers, level 4”. The computer tells you how long this will take, and then sets about it. “2 days, 13 hours, 35 minutes”. And then does it. No further user input required.
No pressure either. If you get half way through, and say “Man, I wish I was learning Cybernetics 2 instead”, you just select Cybernetics. Your progress towards Missle Launchers 4 is saved. There is no penalty for switching as frequently or infrequently as you like. You lose nothing.
And thus are skills learned. No user further interaction required. Heck, you don't even have to be online as it trains. Players can (and often do) set up some complicated skill training, and then go on vacation, secure in the knowledge that it will be done when they get back.
For CCP, (the company behind Eve) this makes a lot of business sense. Since one of the costs of running a MMO is the bandwidth required to allow some crazy number of people to connect to your servers, if you can figure out a way where they can still feel like they're progressing, without actually using up bandwidth, then hooray! You've cut a cost!
The one seeming oversight in this is that you can't queue up skills. You can't pick a skill to train, and then another one to train when you're done. And while you can log in to their web page and see various stats about your characters (including what they're currently learning, and how long until they're done) you can't actually set new skills to learn from the web.
In fact, the only way to set a new skill to learn is to log into the game and set it. Of course, you can then log right back out again, but for changing skills, you have to be in the game, however briefly.
On the surface, this doesn't seem like much of a game. More like a minor mechanic in a larger game. And that's partly true. Skills feed in directly to the rest of the game of Eve, and underly almost everything you do. Without the appropriate skills, you can't fly ships, equip equipment, or manufacture goods. Nearly every action in the game proper has a tree of skill requirements behind it. In addition, many give passive bonuses to all manor of things, ranging from the strength of your shields, to the prices you get for selling things.
It's easy to see the game in flying your ship around and USING the skills you've learned. But what I've gradually come to realize is that, as passive as it seems, the act of learning skills is a game in and of itself. It's just harder to see because the game board isn't on the computer; the computer is just keeping score.
The revelation I've had recently is that the game the “skill game” resembles the most is actually Tetris. Except, the blocks are made out of TIME:
The optimizing part of my mind wants to be training skills as much as possible. In a very real way, the number of skills you've trained represents how “advanced” your character is. So it makes sense to try to always have a skill training at all times. And the optimum strategy then seems fairly straightforward: Whenever you finish a skill, you want to be there, ready to switch over to a new skill right away, since any time between when the first skill finishes, and the second begins, is “dead” time, that you're not getting anything for. (Which offends the part of my brain that loves to optimize, very much indeed.)
The problem, of course, is that the blocks of time necessary to learn skills don't align with the parts of my life when I'm around and available or willing to log in and change a skill over.
So I find myself with an interesting optimization problem. I have a number of skills in the game I can learn, each with an associated block of time. I might have some that take one hour, some that take 5 hours, some that take 9 hours, etc. And then I have to figure out (HAVE to figure out, the optimizing part of my brain demands it, in no uncertain terms!) how to align those in such a way as to line up with the rest of my life.
Like any person (who hasn't been consumed by the game utterly) there are certain boundaries that are inviolate.. I have to go to work most days. Sometimes I have to stay late. Sometimes I know I'll go out and hang out with friends afterwards. Sometimes I DON'T know I'll hang out with friends afterwards, but I suspect it might happen, I require 8-9 hours of sleep every night.
These things aren't changing. They are requirements that I'm not willing to sacrifice for the sake of a game. And they form a game board, of sorts.
“Ok,” my brain says. “We can work with this... So you know you won't be hanging with friends tonight because you want to work on your programming? Ok. Train the 9 hour skill, and change it when you get back. What? You're working late tomorrow? Set something that takes 22 hours before you go to bed tonight.”
And so on.
It really is rather Tetris-like when you think about in those terms. I'm given an irregular shaped board. I get an every-changing sequence of pieces of varying size. I'm rewarded for packing them together as tightly as possible. Except... the irregularly shaped board is my social life, and the game is played on a time scale that takes days or weeks.
It really is aimed squarely at whatever part of my brain loves tetris and games like it.
It makes me wonder, too. What other games could you build, that use something personal to the player as a sort of game board? I've heard about games that use the contents of your hard drive, or of random CDs, to generate levels or monsters. But this one feels unique because it's using things that aren't even directly connected to the computer. What other games could someone come up with that blur the line of “how far can a computer game reach?”
Neat stuff to think about at least, even if I haven't come up with any great ideas in that direction yet. It's still kind of inspiring to see how they managed to pull it off. I wonder if it was intentional.
Read more!