It's a Mod, Mod World

For computer game developers, encouraging users to modify copyrighted material is good for business

6 min read

Id Software's popular Quake III [top] has spawned hundreds of mods, including this bloodthirsty bunny [bottom] by pseudonymous gamers Black Cat and Marauxus. TOP: ID SOFTWARE/BOTTOM: BLACK CAT AND MARAUXUS

People live—they don't just play—the new game called The Sims Online. Its appeal lies in its malleability, as is true of its PC-centric predecessor, The Sims, a people simulator that is the best-selling computer game of all time. Players design their alter ego Sims characters from the DNA up, dictating not only the color of their skin, but also the style of their sofas. Some players are even hacking into the game to allow their characters to appear in the buff.

For Electronic Arts (Redwood City, Calif.), publisher of The Sims, this extensibility is not just novel, it's smart business. In fact, it's the culmination of a trend that has been building in the game industry. By permitting players to modify copyright-protected contents of a game, developers are garnering loyalty from their consumers—and ultimately profits.

When fans get "under the hood," they become vested as co-creators and help to extend the products' shelf life. That's because the US $10 billion game industry, much like the film industry, is built on franchises, or brands, like The Sims, Doom, Grand Theft Auto, and Half-Life. The more heavily gamers are committed to the brand, the more likely they will be to buy the sequels, add-on packs, and other merchandise that the game developer produces.

One company at least, Valve (Kirkland, Wash.), the developer of Half-Life, realized this potential when it saw that a mod (in game speak, a user-created modification) called TeamFortress was downloaded from the Web over 3 000 000 times. Now Valve, after striking a deal with the college students who created the mod, is breaking new ground by releasing a retail spinoff that is likely to sell for the standard $50 computer game price tag.

Valve also offers a way for mod makers to cash in on their creations. Its broadband distribution program called Steam gives "mod authors a direct, low-cost channel to sell and market to their customers," says Valve's chief operating officer, Scott Lynch. "This should have a big impact on the community's ability to generate revenue from their product development."

Art, maps, and engines Three main elements work together to make a game: the library of source art, map files, and the game engine. Graphics and sounds are contained in source art libraries. Map files dictate the layout of the graphics on each level of the game and triggers for various events. And the game engine controls how those graphics are displayed on the screen. Developers of a game can create these three elements themselves or license anything from a comic book hero like Spider-Man to a soundtrack by the rock band Aerosmith, to even the engine at the heart of the game.

Mod makers implement their changes through a variety of programming feats. To create a new character for a Half-Life mod, for example, fans first use the software development kit, which Valve makes freely available on the Internet, to remove the code relating to a chosen creature's shape and movement. Any of a variety of free animation programs online are then used to alter the creature's appearance, say, transforming a zombie into an anthropomorphic hair ball, while the brains of the game, the graphics engine, remain intact. Sounds, graphics, and even entire new levels of the game can be modified or added in much the same way.

Mods dos and don'ts Some of the most successful game developers in the business explicitly permit such modifications as part of the user license. They include Valve, Blizzard (creators of the strategy games Starcraft and Warcraft), and Epic Games (designer of the shoot'em-up Unreal Tournament). Id Software (Mesquite, Texas), which makes shooters like Quake and Doom), goes a step farther. It makes the source code for its previously released games' core utilities programs and level editors available for free download from the company's Web site; this allows for more sophisticated mod making, such as altering not just a monster's appearance, but its behavior. (The graphics engine is more closely guarded, however, and commercially licensed.)

In the standard user license that comes with Half-Life, Valve allows mod creators to freely distribute their creations to other gamers who have already bought Half-Life or other compatible Valve games, but stipulates that they cannot charge for their mods.

User licenses like Valve's are fairly standard in the game industry and require little more of users other than that they own a copy of the game CD-ROM. "Beyond that, as long as they're using and modifying content from within the game, they're free to do whatever they want," says Id CEO, Todd Hollenshead.

Within reason, that is. If someone were to add Bart Simpson to an Id game and market it, Twentieth Century Fox, which owns The Simpsons trademark, could come after him.

For ambitious gamers, making mods is valuable development experience. "It is essential to learn and practice game design before starting your very own game engine," says Andres Reinot, the creator of a popular modification for Quake III: Arena, based on the 1999 movie The Matrix. "That is exactly what mods are so great for: design, instead of laborious [engine] development."

For the companies, mods can increase the bottom line. "Modifications give the game legs," says Jay Wilbur, vice president of Epic Games (Raleigh, N.C.). "After a while, playing the same levels over and over again gets tiring. Now we have a community that will provide new and exciting levels, so the game's life is extended on a player's computer." Quake III: Arena, a shooter released by Id Software in the fall of 1999, is still one of the most played—and modified—multiplayer games on the Internet.

Despite the advantages, major publishers like Nintendo (Kyoto, Japan) and Microsoft Corp. (Redmond, Wash.) have yet to embrace the marketing potential of the mod community. Ostensibly, they're protecting their interests; but they might miss out on a greater market share.

Legal tussles The benefits of software modification by the playing public date back to Doom's December 1993 release by Id. Software modification went into overdrive then, thanks to the openness of the programming structure—which stored the image and sound files in an accessible and separate directory—and the wide-open distribution network of the burgeoning Internet. Id, however, without a user license to govern the distribution of these early mods, had no control over how mods of its games might be represented or even sold. Only later did Wilbur, Id's business manager at the time, post an agreement on the Internet that defined how its interests could be protected, while still encouraging the mod community.

If you design a Doom modification, Wilbur wrote, you need pay no fees or royalties to the company, but you could sell your mod for a fee. However, "your utility MUST not work with the shareware version of Doom; you MUST represent that your utility is not an Id Software product and Id Software cannot and will not provide support for your product, nor for Doom after the data has been changed by your product."

"I am sorry to have to resort to [this message]," Wilbur concluded, "but... there is no other way to keep this process under control."

Before long, there were literally thousands of user-created Doom mods flying across the Internet, ranging from a Star Wars mod to one based on a player's high school. At first, such creations were seen as a true win/win scenario: gamers felt vested in the products, and Id Software reaped the profits of a vested fan base.

Then in 1995, the inevitable happened. WizardWorks Group (Minneapolis, Minn.), an independent publisher, released D!Zone, a collection of 900 user-made Doom mods. Though Id Software owned the copyright to the original game, the modifications were up for grabs. Almost overnight, the D!Zone CD-ROM rose to the top of the PC games sales charts, surpassing the Doom game itself, and earning millions of dollars for WizardWorks.

Id wasn't protected against such exploitation, but the courts eventually intervened. A landmark case came in 1998 after Micro Star Software (Carlsbad, Calif.) released a D!Zone -style compilation of user-created mods for the popular shoot'em-up computer game Duke Nukem. FormGen, Duke Nukem's publisher, tried to assert that Micro Star was infringing on its copyright by selling derivative works—in this case, commercial titles based on the original Duke Nukem release. To FormGen's surprise, a U.S. District Court (Pasadena, Calif.) ruled that the Duke Nukem mod compilation was not a derivative work and therefore did not infringe.

But in an appeal, Ninth Circuit Judge Alex Kozinski in San Francisco ruled in FormGen's favor, preventing Micro Star from selling any more copies of the game and forcing it to pay several hundred thousand dollars to FormGen. Kozinski found that because "the displays assumed a concrete or permanent form in the map files, they were derivative works." The ruling set a precedent: no amount of modification to a copyrighted or patented game element voids the owner's rights.

Foggy Future In the future, attorneys expect that intellectual property issues could get sticky when it comes to game consoles like Sony's Playstation2 and Microsoft's Xbox. In the past, it was legal to reverse-engineer, say, the operating system of the console to develop new games for that machine. The Digital Millennium Copyright Act of 1998, however, states that it is illegal to circumvent technology that controls access to a specific work.

"Reverse-engineering is essential to competitiveness and a key toward making our economy go," says attorney Andrew C. Greenberg, of the law firm Carlton Fields (Tampa, Fla.), himself an IEEE member and a former game developer . "Now we've got the pendulum swinging back to control access to content....We haven't had a mod case where a kid gets sent to jail for making an Xbox mod, but it's become dangerous territory. The copyright law has now turned what was a bright line into a very gray area where it is risky."

To learn what kind of intellectual property is worth patenting, go to //WEBONLY/wonews/feb03/ip.html

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