When it comes to genres, puzzle games are the hardest to get right. Not only are there the inevitable Tetris comparisons (there, we've done it already!), the games also have to possess the immediate, addictive qualities of crack cocaine sprinkled with icing sugar, so you're hooked straight away. And there also has to be a long-term challenge.

Yet, despite alarmist calls to the contrary, games don't (yet) rewire your nervous system the way narcotics do. So if a game is boring the twentieth time you play it, you don't have any compulsion to pick it up for the twenty first time.

It was a thought that struck me at 3.30am last night as I played Gunpey. Clearly, it's a game with some addictive qualities. But after having played one level for 23 minutes, I couldn't wait for it to end. I couldn't bear to deliberately force myself to lose, so I just played badly for a bit longer. But I've had no compulsion to pick it up since.

And that says a lot about Gunpey's status as a glass half-full, half-empty-sort of experience.

The game's basic mechanic is very neat. On a 5 x 10 grid, you have to build lines that stretch from one side of the screen to the other by moving four types of line block – diagonal up, diagonal down, angle up and angle down – that rise from the bottom of the screen, up and down their column. You can use the stylus or buttons, but stylus is definitely best.

The trick for success is to build big combos by creating multiple, fragmented lines that when triggered remove the maximum number of blocks from the screen. However, as things get frantic as blocks approach the top of the screen (that's the Game Over condition), you'll also find the skill of quickly throwing together simple five block lines another necessity.

One nice thing about Gunpey is the way it lets you use the whole of the playing area, and hence control the game's pace. If you want, you can just create short, simple lines. You'll play for a long time but you won't score many points, although there is a bonus whenever you completely clear the screen. Equally, you can mix this style with carefully constructed, highly complex, twisted lines, which are just waiting for their final block, or perhaps some skillful last minute re-organisation, in order to fire off.

This is a particularly good tack to take if you're playing using the break rule, which see blocks disappearing and those above dropping down to fill the gap once a line is formed. For example, it provides the opportunity for drop-down combos, which occur when you create a line that goes on to create another line as blocks fall down the screen.

You can also choose to play the original mode, where lines are replaced by empty blocks. Throughout, Gunpey is full of such options.

The most obvious example is an arrow button in the bottom right corner of the screen. It acts a speed-up, immediately loading new blocks onto the bottom of the screen. You don't get extra points for using it though, so it suggests the designers weren't sure how fast the game should play.

Indeed, while there are various different speed and hardness options, and loads of different modes, such as Versus, the career Frontier mode, Time Attack, Stage Attack, and both two-player and four-player local wi-fi multiplayer modes, Gunpey feels a bit fragile.

Everything's beautifully presented, with lots of skins, funky music, and quirky characters to joust against in Frontier mode. Clear multiple blocks and you'll get to launch special attacks too. But somehow none of these many options really convince when compared to the standard 'Endless' mode.

In fact, the most fun to be had with Gunpey is playing the Endless mode using double screens. This forces you to control the pace of two games – one on the top-screen and one on the bottom – with you hitting the rotate button to switch between them. In this case, the arrow button finally does become important, because you'll probably want to play one screen quickly – using it to build up big combos – while letting the other operate at the default speed.

But one part of one mode isn't really good enough to recommend an entire game. In this, Gunpey feels very much like Meteos, which was the first DS puzzle game created by its developer, Q Entertainment.

Gunpey is based on a nice idea, but one that's been stretched in too many directions without ever approaching puzzling perfection. Less crack cocaine then, more like a box of hit-and-miss chocolate liquors.