Detailed instructions for working a group puzzle of type 'Sudoku-Xtreme'

The 9 elements in each group of this type of puzzle are: 1, 2, 3, 4, 5, 6, 7, 8, and 9.

Every group in the puzzle must contain exactly this set of elements.

Each row in the upper left, upper right, lower left, and lower right puzzles is a group numbered as shown in this Sudoku-Xtreme figure.

In a Sudoku-Xtreme puzzle, each row in the upper left, upper right, lower left, and lower right puzzles is a group numbered as shown in the figure above.

Each column in the upper left, upper right, lower left, and lower right puzzles is a group numbered as shown in this Sudoku-Xtreme figure.

In a Sudoku-Xtreme puzzle, each column in the upper left, upper right, lower left, and lower right puzzles is a group numbered as shown in the figure above.

Each 3x3 square in the upper left, upper right, lower left, and lower right puzzles is a group numbered as shown in this Sudoku-Xtreme figure.

In a Sudoku-Xtreme puzzle, each 3x3 square in the upper left, upper right, lower left, and lower right puzzles is a group numbered as shown in the figure above.

Each diagonal in the upper left, upper right, lower left, and lower right puzzles is a group numbered as shown in this Sudoku-Xtreme figure.

In a Sudoku-Xtreme puzzle, each diagonal in the upper left, upper right, lower left, and lower right puzzles is a group numbered as shown in the figure above.

Each row in the center puzzle is a group numbered as shown in this Sudoku-Xtreme figure.

In a Sudoku-Xtreme puzzle, each row in the center puzzle is a group numbered as shown in the figure above.

Each column in the center puzzle is a group numbered as shown in this Sudoku-Xtreme figure.

In a Sudoku-Xtreme puzzle, each column in the center puzzle is a group numbered as shown in the figure above.

Each 3x3 square in the center puzzle is a group numbered as shown in this Sudoku-Xtreme figure.

In a Sudoku-Xtreme puzzle, each 3x3 square in the center puzzle is a group numbered as shown in the figure above.