Sokobond • Eurogamer.net

To me, the best puzzle games feel like they've been discovered, not designed. Like they've always been there, waiting for someone to come along and uncover them. In the world of puzzle games, developers like Drop7 co-creator Frank Lantz are scientists or explorers, unearthing perfect gems which shine with a complexity that unfurls from a set of simple rules which, once you've grasped them, feel like natural laws. Sokobond is one of these puzzle games - and fittingly, when you start playing it, it feels like a game you've discovered, too.

That's because you learn it without tortuous tutorials. It opens without explanation, just the opportunity to play and experiment. Three circles are sitting on a board of squares. Two of them are red, each with an H displayed in its middle and with a single little orb orbiting it, and one is a blue O with two orbs. One of the Hs bears a dotted rather than solid circle and you can move it around the board with the cursor keys. Soon enough, you learn that if you move a circle next to another and they both have orbs, they'll bond together and an orb will disappear from each. A few moves later, you'll have manoeuvred each circle into a cluster and discovered that the object is to remove all the orbs, leaving you with a little structure.

I don't know much about chemistry, but I guess some of you will have immediately worked out what Sokobond is really about. The circles represent atoms - the H circles are hydrogen, the O is oxygen, and when you've put them all together you've made water: H2O. Perhaps this is why the game feels so elemental, if you'll forgive the pun. It plays upon the rules of the elements, and in each level you'll be making a molecule, from hydroxylamine (NH2OH) to ethanol (C2H6O), their configurations defined by the number of bonds the atoms can carry.