The goal in Mondoku is to completely fill the gridded playing field with numbers. Each number should appear only once per row and column.
Unlike in classic Sudoku, the squares can be of different sizes. Don't let this distract you. If a number field extends over more than one row or column, the rule remains that the number may only appear once per row/column. Fill in the remaining fields accordingly.
The level of difficulty in Mondoku varies depending on how many numbers have to be filled in the grid. The easier levels start with numbers 1-3, while the most complex levels include numbers 1-9. The size of the playing field is also important. Mondoku does not follow the 9x9 pattern, instead it can have different sized playing fields due to the varying sizes of the number fields.