First it's a butterfly you're after. Then a pencil. Then it's a shoe and a kebab and an umbrella; then a penguin, a tricycle, a pachinko machine. A synchronised swimmer, a lawnmower, a traffic light. You think that these will be enough, that they will satisfy your sticky urge. But they don't. There are tractors and phone booths, baseball teams and elephants. Windmills, oil rigs, brontosauruses. It's never, ever enough.
In Katamari, you are the tiny alien pilot of a super-sticky ball. Whatever it touches - if it's small enough - becomes attached, enlarging your ball and snaring progressively bigger items as you go. And it really is everything you touch. You'll lift the chalk drawings off pavements, the signs off shops and riders out of sidecars. Reach the required size within the time limit and the King of Space will convert your huge ball of junk into a star as a reward.
The control scheme uses both analogue sticks, rather in the manner of tank tracks. It takes a little getting used to, but the sense of balance and inertia the system provides makes the game as wonderfully tactile as its premise suggests.
There's a wealth of subtlety within this one-joke format. Big isn't necessarily better. The levels form vast mazes, with areas phasing from inaccessible to accessible to inaccessible again as your ball becomes first big enough and then too big to fit through doors and passageways. It must have required rather more meticulous planning than the airy freedom of the levels suggest. Katamari's remarkable engine doesn't ignore the lumpy physics of your ball, although it does smooth them out considerably. That means sticking on a couple of early lamp posts turns you into something more like a stilt walker, lurching forward in uneven tumbles. It makes ball control harder, but can give you a leg-up to higher areas.
There's a fair bit of variety shuffled into the basic game - including levels where you have to collect a particular class of object instead of simply reaching a target size - and the entertaining diversion of a twoplayer deathmatch. The camera is the only let down, although a bird's-eye view and quick-flip manoeuvre will get you out of most blind spots. When so many games are trying to defend their value by cramming every style and mode into one unpalatable mix, it's refreshing to play something conceived with such vibrant, capricious clarity.
Katamari Damacy is out now in Japan. It has not been confirmed for the UK