Guitar Hero revolutionized the music game genre on home consoles and now Activision and Vicarious Visions are looking to give the same treatment to the Nintendo DS. Guitar Hero On Tour features the same gameplay that Guitar Hero fans know and love, but is designed in a way to make it work for a handheld.

The first question should be obvious: How the heck do you plug a guitar into the DS? Red Octane, manufacturers of the guitars for the console games, came up with a grip for the handheld that feature four guitar fret buttons, one less than the standard five-button Guitar Hero guitar controller. The grip includes: a velcro strap that can be adjusted to fit, a guitar pick and storage slot, and a reversible skin inside the grip that can be customized. The device plugs into the Game Boy Advance slot on the bottom of the DS, and will ship with an adapter that will make it compatible with both the original and Lite models of the Nintendo DS.

According to Activision, the DS guitar grip only has four buttons since it found that to be the magic number in terms of fun and usability, taking handheld (and therefore, screen) stability into account. Activision said it had prototypes of units with three, four, five, and even six-button units (the company labeled Guitar Hero DS a "crazy experimental R&D project") until it settled on the current model. Even with one less button, the development team is claiming that the game is still "freakin' hard" on expert difficulty.

The game is operated by slipping your hand into the guitar grip and holding the DS vertically, much like you'd do in a game like Brain Age. Notes scroll down the screen on the top screen, just like they would in Guitar Hero on your television. During gameplay, the touch screen shows a representation of a guitar. To play a note you need to hold down the proper fret buttons and strum across the screen. From the looks of the presentation we saw, back and forth strumming, sustains, and whammies, were possible by holding and zig-zagging the pick on and across the touch screen. Vicarious Visions claims that the action is "very similar" to picking and strumming on a real guitar.

Star Power can be activated in two ways. For those with no shame, once the Star Power meter is at least half-full, yelling into the microphone will turn on the juice. For those that would rather not embarrass themselves, tapping the Star Power meter on the left side of the touch screen will also activate the score multiplier mode.

Guitar Hero On Tour will be similar in structure and progression to Guitar Hero III on the Wii, but includes new modes. One of them is modeled after battle mode multiplayer in GHIII. Duel mode in On Tour, which Activision is calling "very important" to the game, has the same spiked power-up notes as the console version, but the attacks are much different. Some of them are brand-new, and others taken from GHIII have been changed to take advantage of the DS touch screen.

The first new duel mode attack we saw was "sign my purse." When a player gets hit with this attack, a lady's purse blocks the guitar on the touch screen and must be scribbled on (or rather, "autographed") before they can resume strumming on the guitar. Later we saw that other objects also appear to get signed, like a T-shirt. Another attack will set your opponent's guitar on fire. The only way to put it out, and start playing again, is to blow into the DS microphone a few times.

Returning attacks have new twists up their sleeve. The dreaded broken string must now be physically re-strung by dragging a string up the guitar neck on the touch screen. The amp overload now cuts out all the audio while you play, making it harder to follow along with the music. Duel mode can be played against a friend wirelessly or during career in a dedicated single player duel mode.

You can't talk about a Guitar Hero game without mentioning the music list. While a full music listing is not yet available, we did at least see "Are You Going to be My Girl" by Jet and Twisted Sister's classic "We're Not Going to Take It" during the demonstration. There will be 20 songs exclusive to the DS version as well as transplants from Guitar Hero III. The total number of songs is not yet known, but over 100 minutes of music, optimized for the DS speakers and headphones, have been crammed into the game.

Guitar Hero On Tour will be rated E10+ and is set for a release in June.