This must rank fairly high on the list of Things That Shouldn't Work (But Do) alongside such crazy rulebreaking anomalies as jumbo jets, Noel Edmonds and peanut butter and marmalade on toast.
A DS version of a game that's successful pretty much exclusively because it comes packaged with a massive plastic guitar and makes you feel like a rock god. That's going to be completely rubbish and depressing on a handheld, isn't it?
Think again
But the DS is no ordinary handheld and Guitar Hero On Tour is not the cash-in many observers had expected. Like its console big brother, it comes with a large and expensive peripheral that, once you get used to it, makes perfect sense.
The guitar grip accessory is chunky piece of plastic, about the size of a fist, that wraps around the back of the DS and plugs into the GBA slot on the bottom. Holding the DS sideways in book format (same as Brain Training and Hotel Dusk) you slip your hand through the padded strap and let your fingers rest on the four coloured buttons.
Plug and play
Yes, it looks nothing like a guitar and is not entirely comfortable to use at first, but after short period of acclimatisation it begins to make sense.
It doesn't add so much weight to the DS that it becomes a pain to hold, but it's solid enough to justify the £45 asking price.
Other DS accessories such as the slide controller from Mag Kid, the camera from Face Training and the paddle from Arkanoid, haven't been so expensive but we'd have to say the guitar grip is the most substantial of them all.
It also comes with a special stylus shaped like a plectrum, which slots onto the top when you're not using it. Whip it out and you're ready to rock, strumming the guitar strings on the touch screen.
Amped
The touch screen takes the place of the strum bar in the console versions - you don't actually hit the individual strings. Status displays such as your combo meter and star power indicator are also shown here.
When you've got the knack of holding the four coloured buttons and swishing the stylus at the same time, Guitar Hero On Tour plays very much like the console versions.
To play short notes you do a stacatto flick on the screen in any direction. To play a longer note you move the stylus-plectrum on the screen and keep it pressed down for the duration.
You can still do the up-down strumming favoured by expert players of the console games, although left-right might prove to be more a comfortable direction, depending on how flexible (or knackered) your wrists are.
One of the chief differences is that in having only four buttons instead of the usual five, there's a whole difficulty level missing. However, it's better suited to handheld play without the screen-filling nightmare that is Insane mode - you'd have arthritic claws for fingers after half an hour of that on DS.
Masterful widdling
Since the guitar grip's strap and buttons effectively fix your fingers in place, there's no sliding around the frets. If you found the full version a bit tricky, even with four buttons, you might have better luck with it on DS.
Hitting a successful streak of notes will fill your star power bar, which you activate not by moving the neck of the guitar (there are no motion sensors in the guitar grip and, erm, it doesn't really have a neck anyway) but by shouting into the microphone.
This is one DS game you're not going to want to play on the train. You can shout 'star power' or 'rock out' or just do your very best rock scream.
Or you could blow into the mic and hope that sets it off. Either way, the effect is the same as in the console versions, and you'll have a limited period of high-scoring mega notes to compensate for the potential shame of being seen yelling into your DS.
Pump it up
As you might expect for a music game on DS, a pair of headphones or a lead connected to your stereo will help you get the best out of the 30-odd tracks.
We weren't permitted to reveal the full track listing, possibly because there are licensing issues still to be resolved before the game's summer release, but we can confirm that it's not the same as the set featured in Guitar Hero 3.
Instead, it's a 'best of' compilation culled from all previous Guitar Hero titles, with a smattering of DS exclusives. Songs with slightly sweary or suggestive lyrics haven't made the cut - certain raucous rockers have ensured the console versions are usually rated T (for teenagers) in the US or a BBFC 12 certificate over here, and the moneyfolk at Activision are looking to get the DS edition into the hands of a younger, wider audience.
Since all the game code is separate from the guitar grip - it's just a normal DS cart that plugs into the usual slot - there's the potential for updates and special editions in the future.
Clearly the amount of storage space required means that downloadable updates are off the menu, but additional DS carts would be an inexpensive way to prolong the life of the game if it proves to be as successful as it has been on every other format.
Duellin'
The developers have created several multiplayer head-to-head modes - apparently, they're still deciding which ones are going to make it into the finished game.
The basic ones are the same as in Guitar Hero 3 - you can duel against a friend, sending powerups to reverse your rival's fingerboard, cut a string and so on. Frantic scribbling and tapping with the plectrum is required to get out of those sticky situations.
On top of that, there will be some special ones that could only be done on DS, including a mode where you get to sign autographs and send them to other players.
Some sort of Guitar Hero autograph book sounds interesting - assuming it makes the cut, of course.
Hall of fame
The main solo and co-op games are structured exactly like the console versions. There's a career mode, complete with loads of unlockable gear such as new outfits for the avatar that rocks out on the second screen.
Four characters return from previous Guitar Hero titles, and there are two new ones you'll only find on DS. There's also a handful of new venues to play in, although the size of the screen means you won't be wowed by the graphical detail on show.
But that's not what Guitar Hero On Tour is about. It's the Guitar Hero phenomenon in the palm of your hand. No more, no less.
Ok guitar hero on tour seems brill theres just one problem hoe can you play it. Red Octane are saying to keep your hand straight but that way your DS is slanting upwards. This is a realy bugging thing but a part from that I love it . it's just that one thing that's all. I haven't stopped playing but the more I do it hurts even WORSE! .
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