When Tetris was first released, it was a worldwide phenomenon that saw men and women across the world facing a crippling addiction. Since, we have seen many iterations of this puzzle classics, but for some bizarre reason, developers seem to feel they are obliged to add a new and useless feature every single time. We've had 3D Tetris, Tetris with extra blocks, even Tetrisphere on the N64. Every single time, they've ruined the delicate balance that made the original game such a joy.

Puzzle games often suffer from this distressing egomania that forces developers into fiddling with a classic formula. Puyo Pop is no exception. Also known and loved as Dr Robotnik's Mean Bean Machine, Puyo Pop is a colour-based puzzler that challenges players to stack falling, happy-looking blobs in lines of four or more. Though apparently simple, extremely complex layers of blocks can be constructed, leading to ridiculous scores.

Puyo Pop has always been a competitive puzzler at its heart. Clearing your own screen is much more fun when it causes your opponent's to fill up with irritating colourless blobs that take much longer to clear. Puyo Pop Fever's multiplayer remains rather entertaining, and because the single-player mode takes the form of a competitive series of matches between you and various computer opponents, the game always retains a sense of combativeness.

So - what's the catch? What's the extra feature? Well, as the title might suggest, it's a 'fever' function. If you consistently do better than your opponent, your Fever meter fills up, and at its apex, Fever mode takes over. The player is then presented with twenty seconds' worth of pre-built screens of puyos, making it very easy to rack up ridiculous chains and send metres worth of screen-filling translucent blobs down upon your opponent's screen. At worst, this simply cripples them, or you, and leaves no room for response, no matter how refined your skills are. At best, it's an unnecessary irritation.

More coloured blobs

Thankfully though, Fever doesn't entirely ruin the game. This iteration of the Puyo Pop series is still enjoyable, albeit somewhat more frustrating than those that went before it. Indeed, it introduces a new strategic element, forcing the player to keep an eye on the opponent to make sure they aren't countering too many of your puyo offensives and building themselves up for a Fever. Though many might call this a distraction rather than a strategic element, it can add considerable tension to puzzle battles.

Puyo Pop has never been at its best in single player, which is a shame for this Game Boy iteration as two-player puzzling isn't as easy as just pressing start on Controller 2. Nonetheless, it will serve you well for a few bus journeys' worth of on-the-spot play, should you so desire. The main single player mode pits you against various AI players with very distinctive playing styles, requiring you to adapt your thinking regularly.

Puyo Pop Fever is a reasonably entertaining title, but never strays far above average. The Fever feature adds little to the gameplay and if you're anything like me, you'll just find yourself playing the classic Marathon option anyway. Though it is likely to be left forgotten at the bottom of a drawer before long, it won't leave you entirely bereft of entertainment.