"Why Portal is perfect"

It has perfect... sound direction
Portal's computer-voiced guide, GLaDOS,has more of a personality than the vast majority of 'real' videogame characters.That's thanks to the compellingly scriptedbanter she spouts throughout. Sometimes she made me laugh, others she just confused me - once I actually felt truly sorry for her. She evenmade me sick with guilt aboutan inanimate object.

And you've probably noticed I'm even referrering to 'it' as 'her'. Despite the fact she's an artificially created being in an artificially created world, GLaDOS is a perfectly realised character created by a perfectly realised use of sound and scripting.

It has perfect... visuals
Tetris could be a perfect game. There's even a Flash-built, 2D version of Portal that could be a perfect game. But while both these examples are perfect executions of perfectly brilliant ideas, neither uses the most cutting-edge technology. Portal, on theother hand,is gorgeous. It's not a triumph of substance over style, it's a triumph of both substance and style.

It has perfect... controls
Portal could be an unplayable mess. Instead, it's a science ballet. Everything's so pared back that once you really get the game, you can complete feats with a confidence and assuredness that will seem impossible to anyone watching. Portal is such a pure blend of instinct and calculated risk that in hectic moments it can leave you breathless in shaky-handed success like no other game can.

It has perfect... replayability
I won't lie -Portal is short. Very short. I finished the main game in just under two glorious hours, and the advanced tests in about another 60 minutes. But, then, there's still a host of furiously difficult challenges pushing your Portal knowhow to the limit. It always leaves me wanting more.

What's perfect about Portal's replayability is in how it feels to play. Even repeating some of the early levels is a joy, simply because of the pure wonder and relish I get from playing with the warping technology. Portal feels beautiful to play, and there's nothing else on earth that feels like Portal.

It has a perfect... mystery
On the surface, Portal looks clinical and uncomplex. An excercise in puzzle making with some very exciting new ideas. But after just a few levels, cracks appear in the antiseptic environment (and not just through GLaDOS and her mental dialogue) and you start to question exactly where you are.

And that's when Portal has you, totally. It pulls off all the above elements in perfect style, but where Portal succeeds most is in creating a living, breathing and mysteriously unexplained world around an unshakably solid puzzle experience. And one with a brilliant cliffhanger ending...