Katoi or since 2006 Katoiz consists of a 6x6 board build up with tiles. These tiles have 3 characteristics: form (square, triangle or circle), color (blue, red, green, yellow or white) and size (big or small). In the base game you try to make a stack of tiles. To move the tiles around you can move a tile horizontally of vertically if 1 characteristic with the adjacent tile corresponds. To move diagonally, 2 characteristics have to correspond. The rules included with the game have all kinds of variants which mean you can start playing the game with kids 3 years old. You can build up to the full game in several easy to manage steps.