Fill in the grid so that every row, every column, and every 3x3 box contains the digits 1 through 9. The colored extra-regions must contain each the digits 1 through 9.

In each 3x3 box their is a differet rule to follow:

• Upper left - Consecutive Sudoku: All neighbouring cells with consecutive digits have a colored border.
• Upper centre - Killer <=>: Relation signs represent the relation between the sums of the digits in the sub-regions.
• Upper right - Greater/Less Sudoku: The inequality between each pair of digits must stand correct.
• Centre left - Arrow Sudoku: The digit in a circle is the sum of the digits which are marked with its arrow.
• Centre - Magical square: the sum of any row, any column and both main diagonals in this area is always the same.
• Centre right - Product Sudoku: Digits in a sub-region multiply up to the specified number.
• Lower left - Addoku: Digits in the outside equal the sum of the three numbers of the corresponding row or column in the contigous box.
• Lower centre - Killer: Digits in a sub-region add up to the specified number.
• Lower right - Sum Box Sudoku: First two row of numbers add up to the number formed on the third row.

This combination variant was introduced by Cihan Altay at the 1st Sudoku World Championship.

Fill in the grid so that every row, every column, and every 3x3 box contains the digits 1 through 9. The colored extra-regions must contain each the digits 1 through 9.

In each 3x3 box their is a differet rule to follow:

• Upper left - Digital Sudoku: Digits are in digital form, as given below.
• Upper centre - Even/Odd Sudoku: Yellow cells must contain odd digits, green cells must contain even digits.
• Upper right - Consecutive Sudoku: All neighbouring cells with consecutive digits have a colored border.
• Centre left - Sum Sudoku (Killer Sudoku): Digits in a sub-region add up to the specified number.
• Centre - Classical Sudoku: No special rule.
• Centre right - Pips Sudoku: Digits are given as pips, like on dominoes or dices, as given below.
• Lower left - Big/Small Sudoku: Red cells must contain small digits (1 - 4), blue cells must contain big digits (5 - 9).
• Lower centre - Greater/Less Sudoku: The inewquality between each pair of digits must stand correct.
• Lower right - Sum Box Sudoku: First two row of numbers add up to the number formed on the third row.

Fill the grid with the digits 1 to 9. The number in a cell must be the sum or the difference of the numbers in the both cells below the number. Each gray row has no repeated number. Each white row has at least one number that is repeated.

Fill the grid with the digits 1 to 9. The number in a cell must be the sum or the difference of the numbers in the both cells below the number. Each gray row has no repeated number. Each white row has at least one number that is repeated.

Fill in the grid so that every row, every column, every 3x3 box and both diagonals contains the digits 1 through 9. The algraic operations in the cells must be fullfilled.

Fill in the grid so that every row, every column, and every 3x3 box contains the digits 1 through 9. Each clue-number is the product of the two neighbored digits.

Fill in the grid so that every row, every column, and every 3 x 3 box contains the digits 1 through 9. The specified numbers are equal to the product of there horizontally and vertically adjazent cells. (There is no extra constraint that they must be different.)

Fill in the grid so that every row, every column, and every 3x3 box contains the digits 1 through 9. Some rows and columns have numbers. They represent the product of the two ends.

Fill in the grid so that every row, every column, and every 3 x 3 box contains the digits 1 through 9. Digits in the outside frame equal the product of the three numbers of the corresponding row or column in the contigious box.