Sunday, April 24, 2011

Gamism, Narrativism, and Simulationism

The GNS Theory is a model for role-playing games that covers three distinct approaches. Gamism refers to "playing to win", narrativism refers to "telling a story", and simulationism refers to the process of interacting with a consistent world. While the GNS theory itself is considered a bit outdated (the author of the theory now uses the Big Model instead), it still has repercussions when it comes to believability. While it might seem that only simulationism is relevant, both gamism and narrativism reflect different modes of thinking that can also be compared, contrasted, and included in a believable model.

Gamism: Goal Completion
The idea behind gamism is the idea behind "context-free" games or sports: the rules of the game are the rules of the game, and that's it. The goal of the game is to win according to the rules. This is not a problem in a game that has no context or story behind it, but can be problematic when the "rules" don't exactly match up with the "reality". For example, when I analyzed Company of Heroes, I noted that there were many parts of the game that simply don't reflect a World War 2 concept; the technology and reality of the situation is so different that "real" tactics wouldn't work. Hence, someone playing CoH effectively is going to use strategies and tactics that are not at all comparable to real ones.

However, this is not always a bad thing. Gamism only affects believability when the gameplay is itself unrealistic (or at least inconsistent with the presented universe). It's also possible to make games where, for the most part, logical tactics work. The Total War series is a good example of this, because the basics of combat are the same as in reality. The roles of various unit types (spearmen, archers, cavalry) corresponds to reality, and the presence of factors like fatigue and morale allows for tactics that reflect reality more closely than the average RTS. It's not wholly realistic, of course, but it's closer than most games. This means that "real tactics" translate fairly well to Total War.

Really, the objectives of a gamist player and the objectives of a real or in-universe strategist are not particularly different. Each is attempting to get the best results with the resources they have; as I've discussed, strategies that are considered "cheap" in a game would be considered innovative in real life. It's the differences that make it problematic; when the characters and players are relying on different strategies, it cuts down on the possibility for emergent storytelling when "what the characters see" is not "what the player sees". The decisions the player makes would not make sense to the characters, and that is where the issue arises.

If the gameplay elements are explained, then it's acceptable: there's no morale because the units are robotic, weapons function "unrealistically" but consistently, magic works the same way in the narrative that it does in the game, etc. This is because the gameplay is still part of the story, and thus emergent stories can still be generated. The gamist viewpoint is only disruptive to believability if it emphasizes the cracks and flaws in the game system with relation to the setting being depicted; in that way, it can be seen as pointing out errors, rather than being an error itself. If a specific choice doesn't make sense in the universe, it shouldn't be in the rules.

Narrativism: Telling A Story
Narrativism is generally defined as gaming with the intent of telling a story, focusing on things like moral decisions and character developments. It seems to focus more on authorial influence as exerted by the DM, rather than the creation of a natural world. To this end, it focuses on the introduction of themes and morals that the DM's scenarios are meant to evoke or revolve around. To use some examples from The Forge: "Is the life of a friend worth the safety of a community?" or "Does love and marriage override one's loyalty to a political cause?"

Essentially, Narrativism relies on the player's limited perception by making everything outside their perception malleable and random. Even something as simple as a random encounter table or a "fate points"-style reroll mechanic is in some way Narrativist, because it relies on the world changing outside of the player's view. For example, if a player was falling from a cliff and used a fate point, there would be a ledge or branch to catch them. The world changes based on the use or expenditure of meta-concepts. It's a style of gaming that crafts things around the players, rather than putting the players into an already-existing world. In that sense, one can see how it shares concepts with traditional modes of authorship and writing.

While Narrativism has its uses when it comes to ease-of-construction for a DM or game developer, it's not really a "believable" setup in any way. It relies on the world not existing outside what the players can see, which is really one of the most important things about believability: to make a world that feels real, instead of a fictional construct. Obviously there are some times when those kinds of things are necessary, since the DM can't keep track of everything in the world, but the more Narrativism there is, the less plausible the world in general is. It's relying on plot contrivance.

In addition, I personally don't like the concept of Narrativism as "storytelling". The difference between Narrativism and Simulationism comes down to whether the game is treated like a book or like a scenario, and both of those are things that have stories to them. Simulationism is the story of events that are assembled logically, while Narrativism is more based around DM influence. To me, this makes it feel more forced, and hence more fake: while it certainly may be touching to bring up an issue like divided loyalties or priorities, to me it has more impact if it's something that makes sense in the context of the game, rather than simply being delivered with no connection to logical events.

It's almost a cutscene mentality; sure, you had your fun playing the game and doing stuff, but the DM has an agenda to push, and the choices he asks of you are going to reflect that. The idea that character development and so on can only come out of Narrativism ignores the fact that Simulationism is about portraying events, and events are what cause character and plot development, not pre-chosen themes. The idea of a story being chosen ahead of time runs largely counter-intuitive to the kinds of stories that I endorse, specifically the concept of an emergent story.

Simulationism: Creating a Reality
The simplest way to talk about Simulationism is to say it's about being there. It's about being x character in y location with z things to interact with. It's not just the direct setup of Gamism, though, because "being x character in y location" also has roleplay implications and would affect how actions are taken and the game is played. It is centered around being a character and acting as the character would, with all the tools and information available to that character.

Simulationism is the most directly "believable" form of play, in that it is a style that specifically attempts to include the concept of believability. It relies upon making the world deep and complex so that it can be interacted with, whereas Gamism and Narrativism are both concerned with surface elements. In a Simulationist environment, everything needs to exist in case the players choose to interact with it, or in case it affects the players in some other way. Things exist not just because "they can" or because "it makes the world feel more real", but because that's part of the gameplay. Everything can be interacted with, hence everything has to exist.

In essence, the more details there are in a world, and the more fleshed out it is, the more useful it is from a Simulationist perspective. This is because all those details are things that can be used by the player. Even something as simple as timekeeping adds a dimension to the gameplay, and the closer the game is to the intended reality, the more useful it is for getting into the mindset of the character, rather than periodically leaving to adopt the mindset of the game player.

There's not a lot more to say in defense of Simulationism, because it is believability. Believability and all its values are an intrinsic part of the concept. Every other article on this blog applies to the concept of Simulationism. A key point, though, is that Simulationism doesn't have to be totally detail-obsessed; instead, it's just important to realize that every detail added is a new mechanic or concept for the players to work with, and if one really wishes to connect the player and the character, the two must be in a position that their logic leads to the same place.

1) Gamism treats the "universe" as irrelevant, yet its goals are not totally contrary to immersion and believability; as long as the game rules accurately represent the universe, gamism is not incompatible with those things.
2) Narrativism relies upon an authorial perspective, and thus is anathema to believability. It does not treat the world as "real", it treats it as malleable and protagonist-centric.
3) Simulationism is believability, and shares all its values.

Sunday, April 17, 2011

Analysis: Yojimbo

It's time to veer away from game talk for a bit with an analysis of a classically archetypal movie. Its simple premise and approach has led to countless imitators and copies, and it illustrates the immediate appeal of a "natural world" that characters can logically interact with. In addition, its cinematography, while primitive in comparison to today's, nevertheless manages to be effective in ways that modern movies are less concerned about capturing. The movie in question is, of course, Akira Kurosawa's "Yojimbo".

"Yojimbo" is set in a small, semi-isolated village that has recently been torn apart by warfare between two gangsters: Seibei, the brothel-owner, and Ushitora, a more conventional crime lord. Each backs their own candidates for town mayor, and thus the warfare has both an open and discreet nature. Indeed, one major confrontation is interrupted by the arrival of a magistrate, forcing the hired thugs to hide inside to avoid being arrested and hanged.

Into this scenario comes a wandering swordsman, played by Toshiro Mifune. The swordsman learns about the situation from several people, including a farmer, a corrupt policeman, and an innkeeper. The last of these intends to scare him off with his description; instead, the swordsman decides to stay and exploit the situation, stating that "I'll get paid for killing, and this town is full of men who are better off dead." The swordsman then offers his services to Seibei's gang, killing three of Ushitora's men to prove his skill.

Following this, the swordsman (who uses the name "Sanjuro Kuwabatake") goes back and forth between the two gangs, using their fear of him to his advantage in order to demand more money. However, the gangsters are not totally passive, either; Seibei's wife plots to kill him in order to get their money back, and it is only through surreptitious observation that Sanjuro manages to uncover this plan. There's the sense that he's walking on a razor's edge, and is managing to get away with it through cunning and fear. He even gains a crafty rival in the form of the gunman, Unosuke, who is much more clever than his brothers Inokichi and Ushitora and is depicted as being very alert and intelligent when it comes to Sanjuro's schemes.

Sanjuro's downfall eventually occurs when he goes out of his way to help a family escape the town. The gangsters find out what he did (because the family left a note for him) and beat him within an inch of his life. He eventually escapes and leads Ushitora's men to believe that he's hiding under Seibei's protection, leading to a final showdown between the two that results in the latter's destruction. Following this, Sanjuro hides until such time as he's recovered, at which point he sets out to annihilate Ushitora's gang. With this accomplished, he leaves the town to enjoy the peace it has left.

The Character of Sanjuro
Sanjuro is a classic character - the wandering swordsman who combines skill with guile. His primary trait, though, is his decisiveness. It's obvious throughout the movie that he's not doing things randomly, or just letting them happen; he's always finding a way to create a situation to be exploited.

For example, he did not simply offer his services to one faction or the other. He deliberately set things up in such a way that his skill was proven, and then used his skill as a bargaining chip to raise his price. He sets himself up as a commodity that both factions wish to control. Even when he was caught, he used his escape as a way to further his own goals.

However, his plans are not unrealistically flawless or perfect. It's more accurate to describe them as "good enough"; he knows how to manipulate people with some room for error. Other people respond in predictable, but not robotic, ways. It's natural for gangsters to desire a powerful swordsman for their group, after all. It was necessary that he proved his skill with the sword for his plan to work. They do not simply wish to have him join them because he is a protagonist. Instead, his skill with the sword is what makes him important. Similarly, he does in fact lose at one point - when his choice to help the family is discovered, and he is savagely beaten to within an inch of his life. He's not perfect, but he's clever and resourceful.

In addition, while Sanjuro's past is not discussed, he's clearly a veteran swordsman, and his age is specifically stated (almost 40). He possesses a pair of swords (long and short) that mark him as a Samurai, and his clothing bears a clan mark of uncertain origin. Given that information, while the specifics of his past are not given, it's plausible that he's just an extremely skilled swordsman who's recently down on his luck for whatever reason. The information we're given is believable, and the information we're not given is, naturally, left to our imagination to fill in.

Finally, the issue of Sanjuro's morality is a pretty important one. When he comes to the town, most of the people he encounters assume he is a mercenary, referring to him derogatorily and indicating that he doesn't care about the town. However, over the course of the movie, his motives become more clear. He rescues a family at great risk to himself, and gets caught because of it. He spares one of the thugs at the end who begs for his life - the same character at the beginning of the movie who had rejected his humble origins as a farmer to pursue the "short, exciting" life of a gangster. Even though the townsfolk assume his aim is profit, inevitably he's more interested in bringing down both gangs.

However, his moral decisions are grounded in investment in terms of time, potential profit, and risk. He has to go out of his way to do good things, and in the case of the family it's at great cost to him to do so. It's self-sacrifice, rather than simply being a "good option" and taking it. There is a great cost associated with doing good, and that is what makes the choice virtuous, rather than simply "decent" or "nice". In contrast, his choice to spare the son as he begged for his life is also good, but in a more passive way. It reflects his compassion, but it is less about him going out of his way to do something and more about "not killing him". Ultimately, this was a situation where Sanjuro stood to profit a great deal (he was offered huge sums of money to act as a bodyguard), but he chose to give the money up to help people. These are the kinds of decisions that make his morality feel more plausible; he's not good out of convenience, he's good because he thinks it's the right thing to do.

The Scenario
Yojimbo's setup is a classic one - a semi-isolated town with two warring factions. It's been reused in plenty of other movies and games, because it's effective at what it needs to do. But let's look at the elements involved. The unnamed town in Yojimbo is "semi-isolated": the larger government exists, but mostly doesn't pay attention to the town. The arrival of an official, and the threat he represents of bringing the state government down upon them, is a big deal, but on the other hand when that official isn't around, there's open combat in the streets.

The "semi-isolated" aspect is important because it allows for a normal flow of resources and trade goods, but also means that the area can run by its own rules. Sanjuro can interfere because there is conflict, and the conflict exists because there's no state government cracking down on it. The town provides "natural borders" in terms of area of influence, but there's also a world outside those borders to get all the resources that the immediate area can't provide. If you made the area fully isolated, you'd have to explain every resource - food, tools, weapons, clothes, and so on. If you made the area not isolated at all, you'd have to explain why the police or military don't become involved when people are fighting in the streets. It explains the underlying supply issues while still giving the factions and characters room to move around and influence each other.

One important thing that the movie did (and which was copied by Way of the Samurai, a videogame influenced very heavily by it) was to minimize the civilian presence within the town. While one might normally expect a town to be bustling, in Yojimbo the town's population is very sparse. This means that there's a very core cast of characters outside of the two factions' various thugs and goons. Civilians exist, but as distinct characters instead of nameless rabble. This minimizes their role and reduces the number of "loose ends" that might interfere with the main plot. It also makes the civilians who are present more notable and identifiable.

The two factions in Yojimbo aren't exactly morally grey. They're both reprehensible, which is why it's a "good" act for Sanjuro to attempt to destroy them both. They're not differentiated by much more than their important characters; most of them are just criminals and sellswords, with no real underlying ideology or viewpoint differences. In some ways that makes it more grounded; they're not major political groups, they're just two conflicting crime lords. Their followers are in it for money and power. It makes sense.

Cinematography & Depiction
Despite its technical limitations, Yojimbo does a great job in portraying materials and environments - only natural for sets of that style, but it's the kind of thing that gets lost in CGI. Even in black and white, everything looks real. The simplicity of the recording means that it feels largely untouched, which makes it much more tangible than an environment that has been edited or altered in post-production.

The costuming is ramshackle, but never unrealistic; the criminal underlings wear a wide variety of cobbled-together clothing, but it feels natural instead of "these are thugs, they should wear weird things". They dress like people would dress, even when it means being somewhat impractical. It's something a person would do; they don't have to be totally practical 100% of the time, but an impractical decision should be justified by their personality. They stake a lot on their reputations and their personalities, and their clothes reflect that. They're not simple townsfolk, who would have reason to dress conservatively; they're brash criminals, and their viewpoint and society are reflected in something as simple as how they wear their clothing.

One thing I especially liked was the way combat is handled. There's a large scale battle between the two factions that's eventually interrupted (a picture of the scene in question can be seen above in the "scenario" section). Instead of two hordes of screaming, charging warriors, the battle consists entirely of two groups lunging at each other, then retreating. There's really a sense that neither side wants to be the charging group; they're concerned for their own lives, after all. Hence, the scene conveys trepidation and fear while also conveying bloodthirsty intent.

For his part, Sanjuro regards the whole thing as comical, and hence his own fights are much more dynamic. He moves quickly and surely, taking down his foes as efficiently as possible. The contrast between a hardened warrior and an amateurish thug is illustrated by this difference. The reason Sanjuro is a skilled warrior is because of this decisiveness, not just because he's better at using a sword. It's a subtle change that can actually be attributed to in-universe differences. That's one of the major features of the movie's design, really - things that make sense for people to do. The whole concept hinges on it.

The reasons Yojimbo works, I feel, are the result of doing a lot with a little. There's no supernatural elements or ancient conspiracies or super-powerful characters. It's a basic setup, grounded characters, and logical trains of thought. The world depicted is a simple one, and the most "exotic" thing in the movie is a simple six-shooter pistol. Yet it's a concept that grabbed people's attentions because of the way it portrays that world, and manages to be very compelling despite not having outlandish or unorthodox elements to it. It's the plot and the characters that are important, not the bells and whistles.

So, To Sum Up:
1) Yojimbo is a basic setup that's executed in an interesting and compelling way.
2) It's a good example of a movie that uses simple elements to convey a story.
3) It's also a classic "adventure" model, since the movie consists of the main character interacting with the environment and the environment occasionally interacting back.

Thursday, April 7, 2011

Analysis: S.T.A.L.K.E.R.

S.T.A.L.K.E.R. is a setting founded on a short story ("Roadside Picnic") and a film ("Stalker") detailing an alternate reality centered around the Chernobyl disaster. Most gamers know it from video games: "Shadow of Chernobyl", "Clear Sky", and "Call of Pripyat". As a game, STALKER works with a lot of the concepts that I've talked about in the past. It has a central defining element to its setting. It uses realism to make fantastic things seem more notable. Its characters are dressed and equipped reasonably for the settings. It has an open, internally-consistent world. It is one of the purest "reality + weird things" settings available.

STALKER takes place in an alternate reality that is, for most intents and purposes, identical to real life. The primary difference is the Chernobyl reactor, which was used to study psychotropic weapons and technology. These experiments were responsible for creating the Zone of Alienation, a massive area around the plant where strange phenomena arise. This includes unusual or impossible weather patterns, ghostly anomalies, and hostile mutated creatures.

Due to the deadly nature of the Zone, the policy of nearby governments is essentially to leave it alone apart from some minor military presence. However, the Zone also offers rewards for the diligent. Certain hazardous areas of the Zone naturally create artifacts with various magical effects, such as regeneration and increased vitality. This has led to a booming economy for those willing to venture into the Zone and retrieve these artifacts for use in the "real world". The people in the Zone are hardy adventurers who bring whatever they can from the outside (food, clothes, gear, guns) and try to survive in the harsh environment.

So this gives us two concepts. On the one hand, most of the world is normal. On the other hand, the Zone is weird. The setting's technology and basic assumption of human functioning is based on the former, and the defining elements of the game are based on the latter. In this way it can be compared to Demon's Souls: a "normal" world exists, but the game takes place entirely in the "weird" world. Outside of the Zone, the world functions as normal, and this is the source for all the food, weapons, and gear you find in the game - it was brought in from the outside. Compare this to a post-apocalyptic game, where the source of such items is generally based on scavenging and looting ancient items (that are still somehow functional).

The design aesthetic of STALKER is, naturally, based on reality. It's meant to evoke a combination of military surplus and survivalist gear; the equipment carried by the average STALKER is generally stuff a regular civilian can obtain, with the natural exception of automatic weapons and so on. STALKERS, including the player, are outfitted with carrying gear, armor, radiation protection (in the form of gas masks and chemical warfare suits), and everything else they might realistically need in the Zone. It appeals to tangible items, including those that you personally might own or could buy.

The Zone is a classic example of an open, detailed environment with borders around it. It is a detailed, largely self-explanatory ecosystem that the player can interact with. It has three categories of interactive material: people, creatures, and the Zone itself.

The people found in the Zone are generally either adventurers or military personnel. There are three consistent factions of adventurers in the Zone, though others come and go. The Loners are the neutral faction, and consist of independent STALKERs who simply want to make a quick buck and avoid dying. "Freedom" is a group devoted to studying and understanding the Zone, and are generally laid back. "Duty", on the other hand, is a hardcore paramilitary group dedicated to stopping the Zone's expansion. There's also various mercenary groups and bandits that populate the area, but they're less important.

The three main factions reflect three different opinions about the Zone: "like it", "don't care", and "hate it". They also have three overarching personalities: laid-back, profit-oriented/survivalist, and militaristic. This allows for a simple, but broad, spectrum of player identification instead of the usual good/evil split. Players might identify with them based on their goals, or they might identify with them based on their outlook. A player might not care one way or another, but poor treatment by members of Duty would make them support Freedom. It's the kind of setup where there's no "right" answer except for what the player personally thinks.

In addition, the behavior of fellow STALKERs is pretty reasonable. When they're encountered in the field, they're doing something - patrolling, exploring, gathering artifacts, or whatever. In fact, you can ask them what they're doing and they'll tell you, and if they're on their way somewhere you can ask to go with them. It's simple, but it makes them actually feel like fellow inhabitants and not just random spawns. The conversation system isn't particularly in-depth, but it's sensible. You can ask people what they're doing, what's going on in the Zone, etc. In fact, one of the easiest ways to gather information is just to ask people about new rumors. It's a sensible way to interact with an environment, and again it makes them feel like they're part of the Zone, not just random AI characters.

The monsters and mutants in STALKER are one of the more immediately fantastic elements of the series. There are two major groups of creatures in STALKER: animals and humanoids. Both groups are essentially mutated versions of real things; the former consists of mutated pigs, dogs, rats, and so on, while the latter has a bit more diversity and includes psychic creatures, invisible creatures, and giant creatures. While they're fantastic in nature, they're supposed to have real roots - they're either mutated animals or mutated humans, and in the latter case the method of their mutation determines what kind of creature they are.

One of the important aspects of the mutants in STALKER is their contribution to the sensory atmosphere. Due to the open-world nature of the game, enemy encounters are rarely direct in STALKER. Instead, the player must use their senses to detect enemies and avoid being ambushed. The baying of dogs, the growling of "Snorks", and the roar of a bloodsucker are all distinctive noises that allow the player to identify threats and move to engage them. This creates atmosphere by making sound an important, constantly-relevant aspect of the game. It's a natural cue that gives the world more depth, because the player has to respond to it realistically. The open world gives them a lot more freedom to be "realistic" and changes the dynamic of player-mutant interaction.

While there's not a widely-explored ecosystem, the creatures all feel like plausible hunters, at least most of the time. Everything hunts to eat, and if they do manage to kill something they can be observed feeding on it. Bloodsuckers, for example, can be seen taking fallen enemies to their lair, while fleshes (pig-based mutants) will drag mutant dogs away to eat. Like the human STALKERs, they have a purpose within the zone - to survive and thrive. Their habits may be a bit unrealistic and exaggerated, but they're serving a clear purpose in the ecosystem.

The Zone itself has a few naturally occurring dangers apart from its inhabitants. The most prominent of these are the anomalies, locations within the Zone that have strange, dangerous properties. They may be electrical fields, pockets of deadly gas, or air that bursts into flame when something walks into it. In most cases, anomaly fields cannot specifically be seen; there may be a haze in the air or a shimmer of the light, but the danger itself does not manifest until something has entered the field. For this reason, STALKERs (including the player) carry around small metal bolts to throw into the field and set off the anomaly. Through this method a STALKER can plot a course through the safe parts of the field.

The reason that STALKERs even bother with anomalies at all is due to the fact that anomalies spawn artifacts, small items with diverse magical properties. As mentioned, the artifacts are the main reason for the STALKERs being in the Zone at all. STALKERs go into anomaly zones to collect artifacts by using portable handheld detectors (which come in various types). Artifacts can either be used by the STALKERs themselves or sold to corporations and researchers outside the Zone. Hence, the player can often find fellow STALKERs investigating anomaly fields and gathering artifacts. This helps reinforce the sense that other people have their own reasons for being in the Zone.

The Zone's other major danger is emissions, also known as blowouts (video link). These are periodic storms that kill every creature not in proper cover (i.e. underground or a secure bunker). This includes humans and mutants; NPCs as well as the player will seek shelter when a blowout is imminent. In fact, it's possible for them not to, as corpses can occasionally be found after a blowout. The need to take shelter from them is a plot point in Call of Pripyat, explaining why the three main factions all consider the same station as neutral ground.

Anomalies and emissions aren't just random events, at least in a meta-sense. They're believable, explainable events that occur as regular parts of the Zone, and they affect the behavior of its inhabitants in a major way. They provide something for the player to interact with in the same way that NPCs interact with it. It's not a special, scripted event - it's a normal part of the Zone. Without anomalies and artifacts, there's no reason for most people to be in the Zone. Emissions aren't necessary for motivation, but they're a major issue within the Zone and affect the way people and creatures act.

STALKER works largely because it makes sense. Yes, the Zone makes weird things happen, but they're consistent, rather than totally random. This means that human beings (including the player, naturally) can figure things out and adapt to them. It doesn't tell you up front how to deal with anomalies or mutants, but through experimentation, exploration, and talking to fellow STALKERs, it can be dealt with. It has a lot of depth because everything works and everything has a source, and the one thing that doesn't (the properties of the Zone) is basically magic anyways. It's realistic in enough ways that the unrealistic parts seem more meaningful, and it's open enough that the true nature of the Zone and its ecosystem are allowed to influence the player.

So, To Sum Up:
1) STALKER's internal consistency allows the player to meaningfully experiment and interact with the environment.
2) The combination of realism and fantasy makes it seem more tangible and relatable to the average person.
3) People and creatures within the world have natural, sensible reasons for doing what they do.

Saturday, April 2, 2011

Natural Worlds and Player Interaction

One major aspect of game design concerns the nature of the world that a game is set in. In many cases, this world is linear - meant for direct, story-related interaction, and nothing further. In others, the world may be "open", but the game world still bottlenecks the player at certain intervals to complete story related tasks. In a few games, the entire world acts as part of the gameplay, and everything you do has some sort of consequence. This is easier to achieve in an adaptable system like pen-and-paper gaming than in video games, but there's still a few that have managed to pull it off (to an extent), such as the Way of the Samurai series. Speaking of P&P games, I will also be discussing the Renegade Crowns sourcebook for Warhammer Fantasy Roleplay, which specializes in this kind of design.

Let's start off by establishing some concepts. A "natural" world ought to exist in such a manner that it is functional even if the PC isn't there. It should also have a logic to it that makes sense without the explanation of meta-gaming. This is a point I brought up when discussing cities and facilities - the area should feel like people actually live there, rather than as dressing for a sterile playground. The more realistic it seems, the more meaningful it feels to the player; after all, it's more rewarding to interact with something that feels like actual people doing things than to interact with a lifeless culture. To do this, there's a few things that need to be included.

Area Design
If the goal of design is to make an area believable, it needs to make sense. This can extend from a geographic level (water flow, geology, forestation and agriculture) to a settled level (the layout and location of towns and villages). In essence, the area should ignore the meta-concepts of "getting the player to go where he needs to go" and exist in a way that makes sense. If it makes sense for a village to be somewhere, it should be there. It's reliant both on physical logic (the way the land itself would develop) and "people logic" (where settlements would be built, how they would use the local geography, and so on).

Obviously, there's going to have to be restrictions on the area at some point - you can't map everything, after all. The best way to do this is to make borders exist in such a way that the player won't really question them. Islands are a good place to start, due to the obvious natural border of the ocean. The important part, though, is the idea that the player shouldn't want to leave - that there should be enough focus on the area itself that they're not bored and trying to find somewhere else to mess around in.

The commentary for Team Fortress 2 stated that all they needed was a guardrail; they were considering ways to make it less obvious (i.e. not having invisible walls), but the playtesters felt that it was unnecessary because they didn't feel constrained by the level design. There was no reason to go out there because the players were focused on the action happening inside the arena. In a game about exploration, on the other hand, the players are going to be trying to find hidden things, and hence a big fake invisible wall is going to feel out of place.

Basically, an area should make sense in its own right. Here's a giant square of land, everything in it makes sense with no artificial barriers or limitations. While the barriers around the area are more arguable, it's not as big of a deal if the area within the barriers is sensible. The more fleshed out and detailed the area is, the more it's going to feel meaningful and the less it's going to feel like taking up space between missions. GTA and its ilk are perfect examples of games that have a lot of space, but not a lot of detail. In contrast, Jagged Alliance 2 lets you explore every single square of the map (and the buildings are sensibly designed). You can't leave the map, but there's no reason to - the map is where the game takes place. It's about keeping the player focused on the area by making the area itself be important instead of pointless filler.

Factions and Inhabitants
Human interaction and habitation is based on some simple principles. People live where it makes sense to live, and they've got specific things they need to survive and thrive. This includes food, water, shelter, and tools, among other things. To realistically depict human infrastructure, every need should be taken care of, or at the very least every object and item should have a source (in terms of resources and in terms of crafting). The creation of a sensible economic system makes the world feel more "real" by providing a source for the items that are used by a given society.

In addition, people respond at least fairly sensibly to other people; if their actions help them, or are in line with their moral code, they like them more. If their actions are harmful or repugnant, then they will dislike them. The problem with most morality systems in games is that it works off of an "objective" concept, rather than representing the cultural and societal values morality represents. Games that avoid the "objective morality" concept generally prefer to work on a faction-based model, which is more sensible. Group A has x values, Group B has y values. If you help Group A, or do things that have x values, Group A likes you more. This is generally the approach that is taken by objective morality as well, except it blatantly divides people into "good" and "evil" if it does it at all (i.e. townsfolk like you if you're good, bandits like you if you're evil).

In "Way of the Samurai 3", there are four factions: the local governor and his troops, the rebels/bandits, the townsfolk, and the villagers. While a normal game might consolidate the townsfolk and villagers into one faction, WotS3 reflects the fact that the two don't exactly like each other despite both being "innocent", and the missions you take for one group will often put you at odds with the other. In addition, people respond naturally in-universe to your positive or negative reputation. When you have a positive reputation, people call out to you as you pass and their speech is much friendlier. When you have a negative reputation, they flee or attack on sight. In this way your status with them is easily understood even without a specific number telling you how friendly you are with them.

In "Renegade Crowns", one of the major aspects of area creation is creating "Princes", i.e. local rulers who control a few towns and villages and serve as the major movers and shakers in the region. This is done through random roll tables determining their archetype, their values, their goals, and so on. The end result is that their followers and courtiers generally follow their example - a knightly lord whose goal is the extermination of all monsters in the area is going to be different than a bandit king who just wants to get rich. This provides a sensible concept for the PCs to interact with: their goals can be made clear through interaction or reputation, and whether the PCs agree with them or not determines their status as an ally, an enemy, or wholly neutral. If the PCs are great crusaders dedicated to stamping out injustice, a cultist or tyrant will be an obvious foe for them to muster their strength against. If the PCs are heretics themselves, they might choose to ally with them, or attempt to usurp their position.

In essence, factions should be treated as people with their own values and identities. If you agree with those values, you'll get along with them. If you don't, you won't. Whether or not the players agree or disagree is dependent on the kind of character they intend to play, and making it so that the players can actually ally with a group that makes sense based on their priorities (or ignore them all, for that matter) is a simple way to give them more choice than the usual "good/evil".

Resources and Interaction
One of the key elements of a believable world is that it is made up of things that can be interacted with. A ubiquitously necessary abstraction in video games is that most of the world is window dressing, not interactive. Simple elements like trees and grass would have various uses in real life, but in video games they're just decoration. Obviously video games can't be faulted for that, with their various technological limitations, but it influences how the player perceives the game world.

The more things that can be interacted with, the more important "the world" is for a scenario. It adds to the player's toolbox, even if it's something simple like grass or water or dirt. It's something that, conceivably, the player could do something with, and it adds to their available plan-constructing resources. Of course, this goes for people as well - if the players need to assemble an army to do something, that army has to come from somewhere. If the players need a specialist for a specific job, that specialist has to be somewhere. No NPC is irrelevant, because they all might have a use (or act against the PCs).

The ultimate goal is to make the environment relevant to what the player is doing, rather than pointless eye-candy. When a village or town is made believable, it means that all the elements within the town make sense, and this encourages the player to make use of those elements if the need arises. In most video games, 90% of the world (at least) would be entirely pointless. In an adaptable tabletop game, nothing has to be. Anything can be used in a given plan, so the players ought to pay attention in case they need things later. The world has more depth when everything in it is interactive, and creative thinking is encouraged when everything can be used.

Essentially, it's about simple principles. Objects in the natural world have values and applications, and making use of those values makes the world feel more real. It's not always plausible for a video game, but in a tabletop game the GM's adaptability makes it much more possible. Like interaction, the goal is to let the player interact with the world in an intuitive fashion. If the player asks "can I do x", and x makes sense for the character to do, they ought to do it. The more the world "makes sense", the more intuitive their decisions can be, and the more they can apply real logic to the situation.

Gameplay and Story
One of the most important elements about this is the elimination of the barrier between gameplay and story. In too many RPGs (computer RPGs, at least), the gameplay exists as filler between stories. Nothing is really accomplished, you just fight random encounters. One of the key points in "Renegade Crowns" is that the number of monsters in an area is limited (although more can come in through various means). This means that if a lair is cleared out, it stays cleared out, and that affects the environment. A local town that's being terrorized by goblins will be safe if the players drive them away. It provides more context for their action and makes combat into a tool, rather than a distraction.

One important thing that the inclusion of factions in games like Way of the Samurai or S.T.A.L.K.E.R. does is make it so that, for the most part, combat has consequences. There's reasons to run from a fight if you're trying to avoid making people more angry at you. If a game is sufficiently difficult, there may even be a reason to surrender (at least if you care about what happens to your character). One thing that I really liked in WotS3 was the inclusion of an "apologize" button: if you drew your sword and offended someone, you could beg their forgiveness and potentially avoid a fight. This isn't a dialogue option, either - it's a natural part of the game world based wholly on simple actions and reactions. Everything you do in the game world can contribute to people's opinions of you, and while the game does eventually "take the reins" and push you along a more linear story (depending on which path you choose to take), the world also develops outside of that.

In essence, if you use stealth in a game, the story should develop as though you weren't detected. One of my pet peeves is games where after a full sequence of sneaking past guards, the player character jumps out of the shadows and talks to someone. You can see this in the trailer for Deus Ex 3 when the "aggressive method" and "stealth method" lead to the same cutscene. It's not rewarding the player for choosing a harder path, because that would be unfair to people who just wanted to shoot things. A similar problem occurred with the Renegade and Paragon choices in Mass Effect - both of them would "get things done", as it were, so all that changed was the method. If the game was unbeatable if you chose all Paragon or all Renegade, that would be unfair to players who liked that particular playstyle. In both DX3 and ME, using the "adaptive" or "neutral" method is kind of pointless, because it just means you're indecisive rather than actually making decisions based on the situation.

Basically, games should base themselves around natural reactions. If you sneak into a place, the game should reflect that. If you avoid killing people, the game should reflect that. The more "linear" and "story-based" a game is, the less opportunities it has to feel like it makes sense. The player isn't rewarded for their choices if the game ends up ignoring them, and if the choice doesn't matter, why did you let the player make it in the first place? Why provide the illusion of free will only to deprive the player as soon as a cutscene begins?

So, To Sum Up:
1) A believable world allows the player to interact with it in an intuitive fashion.
2) The more sensible and believable a world is, the more the player is encouraged to treat it like a real place.
3) Interaction (whether human or environmental) is guided by simple, understandable principles that players can use to their advantage.
4) Creating a situation where a world is "real" eliminates the divide between gameplay and story by making the former affect the latter.