Just in time for its 30th anniversary, Nintendo added the Game Boy game, Mario's Picross, to its Switch Online Expansion Pack. The portmanteau "picross" refers to the fact that each puzzle is solved by cross -referencing both vertical and horizontal numeric clues on a grid, creating a picture . The game is barely known in the States, though it led to several Japanese sequels. Each puzzle is made up of columns and rows of boxes, somewhat like Sudoku, either 5x5, 10x10, or 15x15. Each row and each column is labeled with one or more numbers. These show how many consecutive boxes in that column or row must be filled in. When all the right boxes have been filled in, a simple picture, like a cactus or frog, will have been formed. Before you fill any boxes, you can accept a "hint," meaning one column and one row are filled in for you—a significant headstart, which I enjoy. To solve these puzzles, you have to use logic to deduce which boxes are the targets. For example...