I'd like you all to meet my Nintendo DS. Her name is Annie. Despite all of her one hundred million siblings around the world, her existence is a lonely, miserable thing. For you see, Annie is sick. She has nothing to play, despite the deafening groans emitted from the shelves of gaming emporiums worldwide struggling against the weight of thousands of Nintendo DS titles, each more mediocre and poor than the last.

Sure – there are some truly wonderful DS titles, but a great deal of them, for lack of any better language, suck. My dear DS, my dear Annie, as a result continues her lowly existence in quiet reflection at the glory days of portable gaming.

Since she was exposed to Guitar Hero: On Tour, something has just been up with her. Maybe it is the legendary, enigmatic sticker with a much-storied history of a black cat, staring bravely from Annie's body that scares away any quality DS title. Somehow, the all-knowing eyes of the black cat pass over Guitar Hero: On Tour: Decades and permit a brief sojourn in Annie's cartridge slot.

Buttons are pressed, noise is made, and there is much rejoicing within the unfathomable lands that are the balance sheets of mega-publisher Activision. After a while, I notice that Annie starts emitting pained screams. In a disgruntled tone accompanied by droning, staticky guitars, I ask Annie if she is okay, before realising that it is no longer 1987, Michael Jackson is no longer carving a bloody path to the title “king of pop” and the Alien Ant Farm cover of his song, Smooth Criminal is the single greatest feature of Guitar Hero: On Tour: Decades.

I come to the conclusion that Michael Jackson is some sort of prophet, who, some decades ago was able to so succinctly describe the plight of my poor Annie, while the headless serpent that is Activision now slithers over incredibly bright caches of gold and riches in anticipation of the further astronomic financial gains that will likely eventuate when the seven thousand and ninth Guitar Hero title is released in a mere half a century.

In essence, Guitar Hero: On Tour: Decades shows less innovation than the crafty individual who realised that a knife is not only a useful tool for slicing open the throats of bickering human beings, but that if said human being is whining about a lack of bread, you can slice the bread instead and give them some to quiet them for a time.

Annie, my poor, disgruntled DS wants some bread. Guitar Hero: On Tour, is a great big loaf of a bread from some heavenly bakery, and Activision are so kindly throwing crumbs to one hundred million DS users, as though each and every one are eager, squawking seagulls. The only difference is that the crumbs, while offering brief sustenance and a brief smidgen of delightfully flawed entertainment are only slightly more appealing than the prospect of starvation.

As each crumb is considered, the tiny innovations which they carry are positive steps forward for the Guitar Hero: On Tour franchise – which while improved over the first title, still has a long walk ahead of it before it truly hits centre stage.

In Decades, players are now able to play through three career modes either as Lead Guitarist, Bass / Rythym guitarist or through a series of frantic Guitar Battles which are frustrating as ever. As can be expected – there is the usual selection of difficulty options – Easy, Normal, Hard and Expert, with “Hard” akin to “Normal” in the fully fledged console versions of Guitar Hero. Each difficulty setting is pretty easily manageable, with “Hard” and “Expert” the most satisfying.

As the game's subtitle suggests, Guitar Hero: On Tour: Decades focuses on five decades of rock and metal – with five tracks from the “Modern” era, the 2000s, 1990s, 1980s, and 1970s each featured, along with three bonus tracks (which are unlocked one by one after career mode is completed in each of the available modes). This leads to the difficulty curve of the game being sporadic, but tracks generally do get harder as you work your way backwards from Ready, Set Go! By Tokio Hotel to Sweet Home Alabama by Lynyrd Skynyrd.

All up the twenty-eight tracks on offer aren't exactly earth-shatteringly awesome, but there is a selection that is sure to satisfy most – with highlights including One Step Closer by Linkin Park, Eye of the Tiger by Survivor, One Way or Another by Blondie, and of course, Alien Ant Farm's cover of Michael Jackson's Smooth Criminal.

Through the DS speakers, audio quality of many tracks is questionable at best, with generally poor quality on offer as a result of massive compression used– making many tracks sound worse than that present in the original Guitar Hero: On Tour. Plugging in earphones or headphones helps makes the songs less grating and noisy, (some even sound ... okay) but anyone who considers themselves an audiophile would probably rather go deaf than be subjected to the horribly encoded tracks on offer with Guitar Hero: On Tour: Decades.

The Guitar Grip that ships with Decades is of the same design as as the one that comes with On Tour, and they're compatible with one another. Most of the problems that were apparent with the Guitar Grip remain – the buttons are tiny, the Guitar Grip can become loose during play, and hand cramps are likely during extended periods of play.

Increased multi player functionality allows complete compatibility and song-sharing between Guitar Hero: On Tour and Decades, with the game not caring which version of the game is used to communicate with one another – songs from both titles can be shared with one another for multi player sessions with relative ease.

Minor interface changes for the touch screen help to make the game a little more enjoyable, but the note highway and animations (along with the game engine) are somewhat unchanged since Guitar Hero: On Tour. Animations are crude and not at all synced to the music, and the costumes on offer are simple and somewhat unexciting – each character has a number of costumes from each era available, and as you progress through the career mode you're subjected to brief narrative-interludes from venue managers using music-industry buzz-words of the time in an amusing, satirical manner.

It is still good for the DS in the sense that Guitar Hero: On Tour: Decades is ... “portable Guitar Hero”, as advertised, but it doesn't feel all that amazing in comparison to the first game on the platform. It feels more like a bunch of downloadable content for the first title, with no really large innovations or new content other than new songs.

The game play is the same, the graphics are the same, the sound quality is worse, the guitar grip is the same, multi player is (marginally) better, heck, even the design of the packaging and sticker-sets that you receive with the package are all exactly the same, with the exception of artists mentioned and cover art.

Guitar Hero fanatics will obviously love Guitar Hero: On Tour Decades, as it delivers what it promises – twenty eight new tracks to rock with while you're on the bus, in the kitchen, in bed, on the toilet, or wherever else your DS follows the game is probably going to offer you five-to-eight hours of entertainment before you've mastered every track, unlocked every costume and guitar, and completed every single song with a 100% rating.

For the rest of you who don't live and breathe Guitar Hero – there's likely to be some enjoyment in Decades (especially if some of the songs on the track-list appeal to you) but there isn't anything amazing in the title that will make you go and want to snap up every-single Guitar Hero game ever made.

If anything is to be sure, Guitar Hero: On Tour: Decades will likely fund Activision healthily through the first half of 2009, allowing them to work on their “more serious” titles before returning to the DS market later this year for more money in the form of Guitar Hero: Modern Hits, which is sure to include more tiny innovations that don't really mean all that much.

Maybe one day we can expect to see Calculator Hero: No Range Found, which turns the DS into a fancy calculator capable of multiplying the profoundly large numbers found in Activision financial together beyond any of the handheld's memory limitations where you can marvel in utter disbelief at the alarmingly large success of something so simple.