Game Taxonomies: A High Level Framework for Game Analysis and Design

A Unified Classification Plane

Taking these three forms, the ludic game, narrative and simulation, we can construct a classification plane as a triangle with one form at each point, as shown on Figure 1. It is then possible, as a heuristic (ie. a useful working tool) for comparing different games and genres, to place games and genres on that plane, emphasizing the relative degree to which they embody elements of ludic gaming, simulation and narrative.

In this scheme we can place avatar worlds and vehicle simulators at the simulation extreme. Early avatar worlds were three dimensional virtual spaces in which a user could be represented by a movable avatar. These worlds rarely presented much to do, however, since they lacked any ludic or narrative content.

Board games and games that do not represent any kind of fictional world, such as Tetris, belong at the game play extreme. These games are very abstract, but still engaging. Tetris can be placed above and to the less narrative side of chess, since chess is an abstracted representation of warfare, while Tetris presents a very active functional model.

	Figure 1. A 2-dimensional classification plane shows the comparative degrees to which a particular game or genre is ludic, narrative, or simulation-based.

At the narrative extreme we place the fixed narrative structures of digital linear movies. Multipath movies hint at game-like interaction by presenting choices for the viewer, while hypertext adventures provide a high degree of interaction in the player's creation of specific narrative experiences.

Action games, strategy games and RPGs incorporate prominent features of all forms, being games, simulators and narratives. RPGs generally have more narrative content than action games, and strategy games have more simulation than narrative.

Gambling and A Three-Dimensional Classification Space

Gaming is often also understood in the sense of gambling. The world of computer gamers usually appears to be very separate from the world of gambling, although gambling companies are certainly game companies that deliver many gambling products as games. To continue with our definition fetish, we can define gambling as: decisions of gain or loss made by chance within a framework of agreed rules.

Chance is central to the idea of gambling. Of course, many forms of gambling have scope for skill; but these can be placed somewhere between gambling and ludic gaming by the definitions presented here. In fact, we can add another point to our classification system and extend our two dimensional classification plane to produce a three-dimensional classification space, as shown on Figure 2.

	Figure 2. A 3-dimensional classification space introduces pure stochastic, or probabilistic, decision processes as a new element of form.

The different points within this space represent different degrees by which a production represents a game, a narrative, a simulation, or a gambling system. For example, the game of poker has elements of pure gaming and also elements of gambling, since it presents a win/lose scenario played according to a rule set, in which chance has a significant impact upon the outcome but within which skill can also have a major role. If we look at the dimension from gambling to simulation, we enter a very undeveloped zone of virtual economies, while the dimension heading towards narrative suggests experiences structured in time but significantly determined by chance.

From Fiction to Non-Fiction Gaming

There is another distinction to be made between games involving the creation of a fictional world and those that do not involve a fictional world. Since this is a range of variation between two extremes, we can represent the distinction as a third dimensional extension of our basic classification space, as shown on Figure 3. We're running out of easily pictured representations, but this can be solved by representing only three of the previous categories, such as the ludic/simulation/narrative classification plane. The result is a three dimensional triangular prism in which we can classify games according to the degree to which they involve pure ludic form, narrative and simulation, and also to the degree that they involve a fictitious world. In this space we can place team sports and game shows as highly ludic experiences, but with no creation of any kind of fiction. Adventure sports, like mountain climbing, caving and diving are similarly non-fictional, but have more of the nature of narratives than of games, being structured in time, usually not competitive and having rule structures concerning safety rather than constituting arbitrary game rules.

	Figure 3. Variations in degree of fictional content are independent of the ludic/narrative/simulation classification of a game, and so are represented along the third dimension of a classification prism.

Military vehicle simulators lie strongly at the simulation extreme, but combine elements of both real and fictitious worlds. The fiction is realized by imaginary (ie. simulated) components like enemy vehicles and battlefields, while the non-fiction elements include accurate functional modeling of real systems, and the use of physical vehicle models as interaction and staging technology.

Live action role-playing, or LARP, games involve performances of game characters in physical space. LARPing may be more or less game-like, depending upon the degree to which players use rule sets. But most of the experience is a form of improvisational theatre in which the players are the audience. Hence LARPing tends to be highly fictional, but lies between simulation and narrative.

From Virtual to Physical Gaming

The last main classification dimension to be considered here is that between virtual and physical gaming. By virtual gaming we mean games that have most of their mechanics processed within a computer and have their audiovisual content delivered by computer peripherals, rather than being played out and experienced in physical space. The continuum between virtual and physical gaming can, like the fiction to non-fiction continuum, be represented as the third dimension of a classification prism, as shown on Figure 4.

	Figure 4. Representing the continuum from physical to virtual gaming forms a game classification prism clearly differentiating live action gaming from screen-and-keyboard/controller-based computer games.

Sports games by this definition are very much at the physical extreme, while current computer games are predominantly virtual. New forms of location based and mobile gaming combine both virtual and physical gaming, often using a computational and mobile infrastructure to support game play action in the real world. Only a small number of technology based games have been developed that use real-world location as a significant factor in gameplay. Perhaps the most famous example is Botfighters, developed by the small Swedish mobile-games studio It's Alive! [7]. The game tracks GSM-cell location and allows players within range of each other to score kills and gather resources to buy upgrades. Portugese company Ydreams have recently launched a Botfighter-like anti-terrorist game introducing the concept of physical sanctuary in certain locations, malls and restaurants. The projects Can You See Me Now and the recent Uncle Roy All Around You, created by the UK mixed-reality performance group Blast Theory [8], both use handheld computers, GPS location tracking, and invisible online players to construct games where fast physical movement and device-mediated teamwork are central to gameplay.

Uses of Game Classification Spaces

So, we have a bunch of definitions, and we can use these to define some classification planes and spaces. Of what use is this in practical game design?

One use is as a high-level road map for mapping out where other design techniques can be applied. It is very important to have systematic principles for knowing where more detailed techniques, such as abstract formal design tools and game design patterns [4, 6], should be applied. The distinctions of the taxonomy also allow us to see where techniques from other fields can be applied. For example, acknowledging the narrative elements of a game indicates where methods for the construction of narratives, heavily developed for film script writing, can be applied within games.

The classification dimensions also allow us to separate concerns. A good example of this is the previously described tension between game play and narrative. Using definitions of game and narrative that clearly separate them as forms makes it clear why there is often a perceived tension between them. The distinction also suggests a more clear-headed approach to resolving those tensions. If we clearly identify which aspects of the game experience are to have narrative structure and which are to be patterned gaming, we can apply narrative techniques at the right level and consider detailed mechanics for integrating narrative with game play. We can also rethink some more fundamental questions, for example, can we define game mechanics that do seriously advance the higher-level narrative?

The classification dimensions also support brainstorming for game ideas. If a new game is placed in a particular place in the classification system, designers can ask themselves about different possible techniques for integrating the different formal aspects of the game. More than this, if we look for areas of the planes and spaces that are empty, we can explore new types, forms and genres of games. For example, in the ludology/simulation/narrative plane, the space between narrative and simulation is quite empty. As a thought exercise, we can explore what it would mean to fill this space. That is, what does it mean to create something that has aspects of both simulation and narrative, but not much to do with game play? What might this feel like as an experience? What will it require technically? Can we have worlds in which the simulation functions interact to create experiences that over time have particular kinds of narrative structure to them? What are the simulation elements needed to facilitate such emergent narratives?

The most obvious use of the kinds of definitions presented here is to follow Doug Church's suggestion of developing a common design vocabulary. This must begin at the highest level, and can save much time and confusion in high levels discussions about what a game project is going to be. The distinctions presented here came out of practical experiences in discussing game design, and discussions that often suffered from confusion due to the lack of a well established design vocabulary at the highest level. This happens a lot in discussions about where games are going, what we can expect to see over a time frame extending five or ten years into the future. New technical possibilities for location-based and mobile gaming present many new possibilities for game form and experience. We need clear languages for discussing and making decisions about these possibilities.

High level taxonomies are also a crucial precondition for defining the scope of game design patterns [4]. While a number of patterns have been identified [6], this is very preliminary work, and the most useful forms of design patterns must be regarded as a topic of ongoing exploration. In fact, this work will be endless, just as the scope of possible games is endless. Our taxonomies must also continue to evolve, as will the kind of heuristic design rules comprising Hal Barwood's "400 Design Rules" [1,2]. All of these tools represent complementary and evolving methods for game design. They cannot yet be regarded as stable and fully validated, but a high level classification system can nevertheless save much time and confusion in game design, and provide a contribution to the eventual development of comprehensive and systematic tools for designing games of ever increasing complexity.

References

[1] Hal Barwood "Four of the Four Hundred 2001", GDC lecture, 2001.

[2] Hal Barwood and Noah Falstein "More of the 400: Discovering Design Rules 2002", GDC lecture, 2002.

[3] Doug Church, "Formal Abstract Design Tools" Gamasutra, July 16, 1999.

[4] Bernd Kreimeier, "The Case For Game Design Patterns", Gamasutra, December 12, 2002.

[5] Craig Lindley 2002 "The Gameplay Gestalt, Narrative, and Interactive Storytelling", Computer Games and Digital Cultures Conference, June 6-8, Tampere, Finland, 2002.

[6] http://www.gamedesignpatterns.org/

[7] http://www.itsalive.com/page.asp/

[8] http://www.uncleroyallaroundyou.co.uk/

[9] http://zerogame.interactiveinstitute.se/