Jb Reed, Bloomberg News
Jarrod Trainque plays "Guitar Hero II" on an Xbox at a Best Buy store in Cambridge, Mass. "Guitar Hero III" came out recently.

The biggest — and loudest — battle in the videogame business this holiday season could turn on a simple question: Who can rock the hardest?

The battle will be fought with controllers shaped like guitars, drum kits and microphones in a category that has become a gold mine thanks to the huge success of "Guitar Hero," a game that makes players who can't play a lick feel like virtual rock stars.

"Guitar Hero III: Legends of Rock," the latest version of the Activision Inc. game, hit stores recently, featuring a new wireless guitar controller for jamming along to original recordings of Pearl Jam's "Even Flow," Guns N' Roses' "Welcome to the Jungle" and other ax-heavy tunes.

But the title, which has dominated the music-games category, will now face a formidable new competitor named "Rock Band," which goes on sale next month. Instead of one instrument for controlling the game, the game has four — a guitar, bass, microphone and drums — to better simulate the thrill of being in a music group.

Although many analysts believe "Guitar Hero's" reputation will be hard to overcome this holiday season, "Rock Band" has two major assets behind it: the creative team that made the original "Guitar Hero," Harmonix, and the deep pockets of Viacom Inc.'s MTV, which acquired Harmonix last year.

The music-games genre has found an immense audience by stretching the boundaries of what videogames are. There have been more than 5.9 million copies sold of the earlier versions of "Guitar Hero" in the United States since the game's first installment was released two years ago.

"Guitar Hero" has also successfully tapped into new audiences, partly by avoiding the mayhem that's common in many games. Activision's own research shows that 20 percent of the users of "Guitar Hero" are first-time players of game consoles, including many musicians.

"Guitar Hero III" and "Rock Band" share a similar concept: simulating a sense of creative participation in the music. The games score players on the precision with which they hit color-coded buttons that correspond to visual cues that flash on their TV screens in synch with songs. Users don't technically "play" the musical notes with their instruments, but if they don't hit the right buttons on their controllers the songs don't sound right. As users play, the games show computer animations of rockers strutting on stage to further convey the mood of a performance.

That feeling comes at a price though. "Rock Band" will cost $160 to $170, depending on the game console a user has, for a bundle that includes the game, drums, a microphone and an instrument that can be played as either a guitar or bass — a steep sum for a single game. "Guitar Hero III" is priced at $90 to $100 for a bundle that includes the game and guitar. Most games, which typically don't come with specially designed controllers, cost $50 to $60.

Analysts predict "Rock Band's" price and lower brand recognition gives "Guitar Hero" a good chance of significantly outselling the MTV game this holiday season. "I think right now the cost is too great for most people," says Michael Pachter, an analyst at Wedbush Morgan Securities.

Activision executives believe "Guitar Hero's" emphasis on a single instrument will give it more mass-market appeal, while "Rock Band" might pull in more hard-core players with its multi-instrument focus. But "Rock Band" can rely on the full promotional power of MTV's music-themed cable channels, including MTV, VH-1 and CMT. In one of the most aggressive marketing campaigns yet for a videogame, MTV plans to pull out all the stops to build awareness among its viewers of Rock Band, weaving the game into its programming. MTV values the promotional time at $30 million.

Rock Band will be set up in the home of the participants of MTV's "Real World" reality-television show. In mid-November, there will be a "battle of the bands" competition shown on MTV's TRL music video show, pitting two groups of gamers that were selected during a cross-country tour. VH-1 has even done a spoof documentary in the style of its "Behind the Music" series, called "Rock Band Cometh: The Rock Band Band Story," which chronicles the antics of a fictional band that plays the plastic instruments from the game.

"It was really easy to figure out how to create awareness, heat and buzz on our music networks," says Van Toffler, president of MTV Networks Music and Logo group.

While Guitar Hero is entrenched in the category, executives at Electronic Arts Inc., the games publisher that's distributing Rock Band on behalf of MTV, say Rock Band has the benefit of the talent that created the original Guitar Hero. "You have to ask, 'which is the cow and which is the milk?"' says David DeMartini, vice president and general manager of EA partners. "I think Harmonix is the cow." Rock Band and Guitar Hero III will both come with greatly improved music. Most of the songs in previous versions of Guitar Hero were covers of rock songs, which somewhat diminished the authenticity of the experience. In contrast, most of the songs on Rock Band and Guitar Hero III are master recordings by the bands that made the songs famous. Both games will allow players to purchase and download extra song packs from the Internet.

Among the musical additions to the new games are the Rolling Stones, which contributed "Paint it Black" to Guitar Hero III and "Gimme Shelter" to Rock Band.

Metallica licensed two of its best known songs — "One" and "Enter Sandman" — for use in Guitar Hero III and Rock Band, respectively. Marc Reiter, who works for Q Prime, the firm that manages Metallica, says the band was previously approached to license its music to games, including Guitar Hero, but never agreed because makers only offered flat fees, instead of royalties based on sales.

With Rock Band and Guitar Hero III, the game makers finally agreed to grant royalties. Mr. Reiter says Metallica is happy about the decision since a couple of them play Guitar Hero, as do their families and fans. "We felt we were remiss in not being in there," he says.