A MARUPEKE puzzle consists of a square grid in which some of the squares are blacked out in the manner of a crossword puzzle. Some of the remaining squares contain either an X or a O. To solve such a puzzle, the solver must place an X or a O into each of the remaining squares in such a way that there are never three Xs or three Os in line, either horizontally, vertically or diagonally. Each puzzle has a unique solution which does not require any guesswork to achieve. Puzzles can be built in sizes from 4x4 up to 10x10.

The following graphics show a Marupeke puzzle in the Crossword Express Solve screen and a PNG graphic file produced by the program's print function, showing the complete puzzle solution. See also a  full size version of a PDF file. 

The key features of the Crossword Express Marupeke Construction function are as follows:-
  • Fully automatic construction of puzzles.

  • Puzzles can be made in a range of square sizes from a minimum of 4x4 to a maximum of 10x10.

  • A multi-build function allows the construction of many puzzles (thousands if necessary) in a single operation.

  • Puzzles can be printed direct to the printer or, if you install the appropriate software, it can be sent to a PDF file. The recommended software for this purpose is  Primo PDF which you can download free from their website,  although you might consider sending them a small donation if you find their program useful. Mac users will be able to create a PDF file directly from the screen provided by the printer driver.

  • Formatted output can also be exported from the Print screen to graphic files which conform to the BMP, GIF, JPG or PNG formats.

  • A fully interactive Solve function is available to allow you to solve the puzzles "on screen" without needing to print them.