20in20 is a math based puzzle game, each level contains 20 tiles and your goal is to mark the tiles in the correct order to get the total value of 20.Mark the tiles by clicking on a tile and drag to the next tile, but watch out for the invalid tiles. Reverse your drag back to the tile you started on allows you to start over. Remember you need to mark all the valid tiles and get the total value of 20 to complete a level.The game consists of 60 hand made levels ranging from Easy to Hard, but it also features a Procedural level system with unlimited levels.If you get stuck you can use the light bulb to get a hint of what path you should take, using the hints multiple times will show you more of the path.