Today Sudoku contains very many types of variant Sudoku, more types of Sudoku puzzles are still under continuous development, please continue to pay attention to Sudoku today.

- Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each of the rows, columns and the nine outlined 3x3 regions.
- A number between two cells indicates the sum of the numbers in these cells. A number between four cells indicates the sum between two diagonally adjacent cells, either top left + right bottom (\) or top right + bottom left (/).

- Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each of the rows, columns and the nine outlined 3x3 regions.
- A number between two cells indicates the sum of the numbers in these cells. A number between four cells indicates the sum between two diagonally adjacent cells, either top left + right bottom (\) or top right + bottom left (/).

- Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each of the rows, columns and the nine outlined 3x3 regions.
- If a shaded cell and a white cell are adjacent then the digit in the shaded cell is greater.

- If a shaded cell and a white cell are adjacent then the digit in the shaded cell is greater.

- Digits have to be place in accordance with the “greater than” signs.

- Digits have to be place in accordance with the “greater than” signs.

- Each set of four digits in the intersection of two lines indicates the digits that have to be placed in the four adjacent cells.

- Each set of four digits in the intersection of two lines indicates the digits that have to be placed in the four adjacent cells.

- Arrows and numbers outside gridding means how many different numbers in corresponding direction grid.

- Arrows and numbers outside gridding means how many different numbers in corresponding direction grid.

- The same numbers are not chess-knight move connected.

- The same numbers are not chess-knight move connected.

- Each number at the intersection of four cells is the sum of digits in those four cells.

- Each number at the intersection of four cells is the sum of digits in those four cells.

- There are some dots between cells. The numbers on each side of a dot must always be consecutive. Not all possible dots are marked.
- Digits outside the grid indicate the sum of the first 3 digits in the corresponding direction.

- There are some dots between cells. The numbers on each side of a dot must always be consecutive. Not all possible dots are marked.
- Digits outside the grid indicate the sum of the first 3 digits in the corresponding direction.

- Consider each number to be the height of a building. The numbers outside the grid indicate how many buildings can be seen when looking in that direction (taller buildings conceal smaller buildings behind them).

- Consider each number to be the height of a building. The numbers outside the grid indicate how many buildings can be seen when looking in that direction (taller buildings conceal smaller buildings behind them).

- Everywhere 2 odd and 2 even digits form a 2x2 checkerboard pattern, a Battenburg marking is given. A checkerboard pattern is a 2x2 area of cells where the top-left and bottom-right cells are of one type and the top-right and bottom-left cells are of another type. All possible dots are marked.

- Everywhere 2 odd and 2 even digits form a 2x2 checkerboard pattern, a Battenburg marking is given. A checkerboard pattern is a 2x2 area of cells where the top-left and bottom-right cells are of one type and the top-right and bottom-left cells are of another type. All possible dots are marked.

- Grey cells in the grid represent many cloned areas. Digits in these areas on corresponding positions must be identical. Cloned areas are only moved, without rotation or reflection.

- Grey cells in the grid represent many cloned areas. Digits in these areas on corresponding positions must be identical. Cloned areas are only moved, without rotation or reflection.

- Cells with shaded squares contain even digits. Cells with shaded circles contain odd digits.

- Cells with shaded squares contain even digits. Cells with shaded circles contain odd digits.

- Rows and columns span across the gaps in the diagram.

- Rows and columns span across the gaps in the diagram.

- Apply Classic Sudoku rules. Within each coloured region each digit must appear exactly once.

- Apply Classic Sudoku rules. Within each coloured region each digit must appear exactly once.

- The connected shaded cells contain each digit from 1 to 9.

- The connected shaded cells contain each digit from 1 to 9.

- The same numbers are not chess-knight move connected.

- The same numbers are not chess-knight move connected.

- Sum and difference of two orthogonally adjacent numbers must not be 5.

- Sum and difference of two orthogonally adjacent numbers must not be 5.

- Each of the four shaded 3x3 boxes contains each digit from 1 to 9.

- Each of the four shaded 3x3 boxes contains each digit from 1 to 9.

- A number between two cells indicates the sum of the numbers in these cells. A number between four cells indicates the sum between two diagonally adjacent cells, either top left + right bottom (\) or top right + bottom left (/).

- The connected shaded cells contain each digit from 1 to 9.

- The connected shaded cells contain each digit from 1 to 9.