I recently bought this game from Amazon, and i was sadly disappoint that it didn't some with a steam activation code so i couldn't get the steam achievements for it, but oh well. I got on with the game and was instantly hooked.

You control the goo balls in the game and use them to build towers or similar things to complete puzzles and allow the goo balls to escape on the other side of the level, usually passed some obstacles.
There are a verity of different goo balls that do different things in different situations.

It is not a common thing that you find such a fresh game play idea so well implemented, the graphics are flawless (How can you go wrong with blobs of goo though) the scenery is charming and the music is toe tappingly good. The story as well, i found myself getting drawn into, half of the game is covered in an air of mystery and all the time you find yourself wondering why... just why... where does this pipe go that the goo balls are so desperate to get to?

Once you finish a level, any goo balls over the required number that you have collected get sent to the world of goo corporation, where you compete with other players to build the worlds biggest tower of goo. The other players are represented by floating clouds.

This game was so good i bought it again in an offer where you pay what you want for it