Sudoku Pro offers additional sudoku variations besides the classical one. You can choose from two grid styles and five kinds of extra regions.
The available grid styles are standard and squiggly. Instead of 9 square blocks the game grid consists of 9 non-square regions. The regions are outlined with a thick line and the digits 1 to 9 have to appear exactly once in each region.
Extra regions impose additional constraints on the puzzle. Besides the classic version there are four kinds of extra regions:
• None: You only have to deal with nine rows, nine columns and nine blocks in either square or squiggly format.
• X-Sudoku: The digits 1 to 9 also have to appear exactly once in the two diagonals of the puzzle. To indicate this the diagonals of the puzzle are highlighted by a different color.
• Hyper-Sudoku: This sudoku has four additional regions highlighted in a different background color. In addition to rows, columns and blocks the digits 1 to 9 have to appear exactly once in each of these extra regions.
• Percent-Sudoku: The sudoku has three additional regions that resemble a percent sign.
• Color-Sudoku: This sudoku has nine additional regions. Each one of these regions is highlighted by a distinct color so there are nine different background colors. The digits 1 to 9 have to appear exactly once in all cells that have the same background color.
Sudoku Pro Ω is free and open source. You can contribute at https://github.com/mariokmk/sudoku