I may have liked Tetrisphere, but I am not a man who believes the puzzle games, like Mario games, can be as good in three dimensions as they are in two.

I am ready to make another obsession.

I beat the tutorial of Picross 3D on a Nintendo DS XL yesterday. I now understand how the superb Picross can work in three dimensions, and I am pleased.

The addictive original Picross presented players with a flat grid. The grid needed to be turned into a picture of a flower, a face or some other silhouette. In order to display that image, players needed to fill in certain squares and cross out the rest. Each level of the game presented a new grid with a new image to be revealed. The only clues about which grid squares to fill were numbers that appeared at the perimeter of each row and column. They indicated the number of squares that should be filled in the row or column. Facing a 10-square line and a number 8, for example, the player had to guess or, better, use the clues based on numbers and filled squares in other rows and columns.

It turns out that this formula works in 3D as well. Yesterday, on a DSi XL at Game Developers Conference that contained Picross 3D, I used the stylus to rotate a beam of blocks. Numbers were on the short edges of each row and column of this beam. They represented the number of blocks that need to be kept in the row or column. The other blocks needed to be tapped into non-existence. I learned these simple rules in a tutorial that had me carving out such simple forms as a capital letter T. Then, I tried a harder part of the tutorial that taught me about circled numbers. Those indicate that the blocks that need to be kept in a line are not all in adjacent. So you have to assume there is a gap.