Over the lifespan of the current generation of game consoles, the first person shooter, or FPS, has risen to become one of the most popular genres among Western audiences. Budgets of the best-selling series have swollen to eight figures to meet public demand for ever-more visceral simulacra of wars contemporary and futuristic. (Historic settings have fallen out of favor.)

"Faster, more intense" was famously George Lucas's preferred direction to actors, but it's an apt mantra for the developers of the ever more intense and glossy single-player campaigns. The thrill and the spectacle have helped to cement a handful of perennial franchises in the consciousness of the gaming mainstream.

But more important still may be the online multiplayer modes where dedicated gamers play in the weeks, months, and years after the fleeting delights of the campaign have faded from memory. For every hour clocked in single player, many gamers will spend days facing off against unseen (though often heard) human opponents in dedicated multiplayer maps.

Though the ensuing carnage may appear wanton, these arenas are carefully crafted to foster gameplay that will, ideally, entertain as much for the 300th time as they did for the third.

To find out how designers go about creating these play-spaces, many of which gamers will come to know better than the insides of their own refrigerators, Gamasutra spoke to some of the masters of the craft: 343 Industries and Certain Affinity, custodians of the Halo universe, and Respawn Entertainment, whose founders created the Call of Duty series and have the upcoming Titanfall on tap.

Ask either 343 or Respawn the first thing they think about when designing a multiplayer map, and they'll tell you the same thing. No map is designed in isolation. No one map can be all things to all players. Variety is vital. "You know that you're going to have multiple maps, so you want to make sure that the assortment of maps covers all different gameplay types based on the modes, objective types, or the weapon sets and vehicles that you have," says Kynan Pearson, lead multiplayer level designer at 343.

In the case of a Halo title, designers will ask themselves if a map should be large or small, the size influencing the ideal number of players, the engagement distances and the weapons best suited to them, and the suitability of vehicles.

As fundamental is the choice between so-called symmetric maps and asymmetric maps. Symmetric maps tend to have either mirror or rotational symmetry about their center, with two opposing teams spawning at opposite ends presented with essentially the same landscape before them. Such maps are particularly suited to end-to-end objective-based game modes such as capture the flag, Pearson explains, affording neither side an advantage due to superior elevation or cover.

Asymmetric maps by their very nature allow for a greater diversity in topography, which lends the maps to other sorts of objective based games that eschew team bases in favor of designated positions to be captured and held. Depending on game mode, these positions may number from one to many, may remain static or change location, or any permutation thereof.

The quest for diversity is a source of inspiration for Geoff Smith, game designer at Respawn Entertainment, who, during his stint at Infinity Ward, designed multiplayer maps for the studio's Call of Duty series, up to 2002's Modern Warfare 2. "Sometimes I'll find some cool-looking location picture online and that will give me ideas," he explains. "Other times I'll look over the game we are making and see what kind of environments or gameplay style is missing. Maybe we have too many long-range maps, maybe not enough close quarters battle types. Maybe we need a different location look."

The ratio of asymmetric to symmetric maps is not a question that will have troubled Smith. Call of Duty is a military title, and one that sets its battlegrounds in the real world. When it comes to favelas, submarine bases, oil refineries, and their ilk, symmetry and realism tend to be mutually exclusive. Symmetric maps are out. This is less of an issue for a Halo title, where players are just as likely to be exchanging fire on, say, a gigantic monument to an ancient alien race drifting through an asteroid belt (as good a description as any of Halo 4's Monolith). Symmetric? Why not?

In the case of a Call of Duty title, though efforts are clearly made to make asymmetric maps fair, a simple tweak of the game rules can ensure balance. Play capture the flag on Modern Warfare 2 and you'll find teams change ends at halftime. These spaces do not exist in a vacuum, but must coexist with both game mechanics and game mode rules.



Call of Duty: Modern Warfare 2

But no one map should be too specialized. "I think you will always have a primary and a secondary [game mode] that you go for," Pearson says. "As long as it works with a team-based and a free-for-all mode, and an objective type, it doesn't matter which one it is, it'll tend to be multi-versatile. You will build maps with certain objective modes in mind to make sure that they're highlights and to make sure they work really, really well, but you don't try to do that at the detriment of other modes."

With this basic spec decided, it's time to begin designing. At the outset, paper is weapon of choice. "To me the layout is the most important aspect of a map, so I might quickly sketch out some patterns and paths on paper to start to figure out how I want the map to play," says Smith.

"When it's on paper it's cheap and easy to riff on and iterate," explains Mike Clopper, lead level designer at Certain Affinity, who collaborated with 343 in the making of Halo 4. "If you start out with an initial basic line drawing, and that's really concentrating on the flow of the map and the main spaces we want to facilitate conflict in. Where are these great clashes going to happen? What are the directions that people are going to take to make those things happen?"

Echoing Smith's sentiment that the layout of the two-dimensional plan is all-important, Clopper explains that the paper design is a crucial reference point when designing the detail in 3D. "It allows us to think back to what the essence of the map is. Sometimes in the 3D realm you can go down a rabbit hole riffing on some of the smaller encounter spaces."