VIDEO / Fundamental blocks: The principle is simple but Tetris and its successors continue to fascinate. Rupert Goodwins on the shape of things to come

The original Tetris video game was remarkable in many ways. It came from Russia, was as simple to play as falling off a bar stool and ruined more evenings than the Stolitchnaya vodka distillery. Lots of little coloured blocks in different patterns tumbled down the screen; get three blocks of the same colour into a line and they disappeared. With sufficient skill you could keep the screen almost empty for minutes, until the increasingly manic flurry of blocks resembled a terrorist attack on Legoland and your fingers fell off.

Tetris 2 (Nintendo) does not make many additions to the game, but they make it a lot more fun to play. Two new sorts of block have been added - flashing and fixed. A sprinkling of both appear at the start of each screen; manoeuvre a falling block so as to dispose of a flashing block and all of the fixed blocks of that colour will disappear. Remove all of the fixed blocks of all colours and you've won that screen and can move onto the next.

Like its predecessor, Tetris 2 can subtly warp your consciousness. Play it for more than an hour and you'll start seeing everything you do in terms of flashing blocks and geometric jigsaw puzzles. Drive to the shops and you'll try and park between two cars the same colour as yours - manage it and you'll be surprised when all three fail to dissolve into glittering sparks with a synthesised chirp of delight.

If you think that the theme of tessellation has been stretched to its limits, you underestimate the ingenuity of the designers. Head-to-head play, using two Game Boys and an interconnecting lead, is going to be next year's big fad.

Monster Max is another Game Boy tour de force; your character is all of a centimetre high and as green as Jonathon Porritt's underwear, but nevertheless it packs in humour and logic.

The items in the game are tiny but easily distinguished. Three types of cube litter the floors of the Mega-Hero Training Academy - electric, moving and alphabet. The first fry our emerald protagonist, but the other two types need to be shoved into various permutations to complete tasks. At times it feels uncomfortably like the sort of tests psychologists put monkeys through - stack the tea-chests to reach the banana.

Lots of other things are scattered around, mostly familiar to anyone who's played this sort of game before. Jumping Boots for extra height, a bag to increase your hefting power, swords and gold and trampolines and joysticks.

Everything has a purpose, except perhaps the relentlessly jaunty music. To the player, it's just an adornment; to everyone else in the room, it's as intensely annoying as Take That's latest opus played on a wristwatch. For hours.

Both games were pressed into service - with obligatory headphones - to keep the family's eight-year-old quiet on a long journey down to the West Country. By Taunton he'd temporarily tired of Tetris 2; Monster Max saw us through to Exeter. Of the two, Tetris has considerably more grown-up appeal, but it's dangerous to underestimate the addictive qualities of Monster Max. It's insidious; after half an hour you'll get stuck on a puzzle and turn the thing off. Later that same evening the answer will pop, unwanted, into your head and the only way of exorcising it is to fish out the Game Boy and play it through.

Tetris 2 from Nintendo at pounds 24.99. Game Boy from pounds 39.99

(Photograph omitted)