World of Goo

The sound is another stellar achievement. From the gorgeous chirrups and gasps the Goo balls make (a splendidly clever means of helping you differentiate different types when things get hectic), to the swelling, evocative music, it's one of the most aurally perfect games ever. Combined with the stretchy, wobbly physics, and tactile nature of everything you can move, it's all so tangible.

And here's the really important bit: the Wii version is better than the PC version. The mouse for Wii remote swap is not necessarily a simple one, but in this case it's seamless. The cursor on-screen is a fat blob with a short tail, easily managed. It's games like this that realise the Wii's magic wand. As Elebits and other games have demonstrated, the remote is perfect for picking things up and flinging them around in a way the PC's mouse cannot quite articulate. And best of all, the temptation to embrace gimmicks has been completely avoided. Everything is on one button only.

Where the Wii version really stands out is through the co-op. The implementation is just sublime. There's no menu option, no restarting a new game, no registering a new player. You can be muddling your way through the gorgeous challenges, and a friend can walk in, pick up another remote, and they're playing too. There's no fuss, no, "New player joins" message on screen. It just hears the electronic hello of a new remote - or three - and up pops a new cursor in a slightly different colour.

To avoid the complete madness of multiple players trying to move the camera around by pointing to the edges of the screen, only the primary remote has such a power. This can lead to confusion, obviously, so you need to communicate. And of course you can mess up each other's plans. But in practice this just leads to more fun. As a friend (who had never played before) and I attempted to complete some of Chapter One's later levels, we fell about laughing as we kept accidentally removing crucial Goos from structures the other was working on. Then, coordinated, we polished off puzzles far more quickly than we could have alone.

There are two immediately obvious applications of the co-op. A group of up to four people playing the game for the first time can all muck in, throwing out ideas, each trying something without having to share a controller, and then everyone piling in once the goal is apparent. Then there's those looking to achieve the toughest OCD challenges - the super-tough optional goals each level sets - who can work together to speed up construction. (Imagine solving the huge tower construction puzzles with four people working together - it's impressive stuff.) And there's a third, perhaps less apparent use. At one point, in one of Chapter Four's glorious block-building levels, I held a remote in each hand so I could stack things on either side without sacrificing balance. Smart!

It's hard to describe criticisms of World of Goo as mistakes, but rather suggestions for improvements. The same ideas for the PC version remain wishes here. It would be great to be able to zoom the camera out to see a level all at once, and there doesn't seem to be a good reason why the "Retry" button needs to disappear once a level's main goal is completed, as you may have fallen short of the OCD aims. And most of all, there's still the occasional frustration of not being able to pick up the specific Goo you're after due to dozens of others rushing past. A way to tell the game you want to get the red balloon Goo, and not the droplet Goos in front of it, would make things even smoother.