Crazy Sudoku

Crazy Sudoku is a Sudoku variant. The rules: The game is played with nine squares which are arranges in a 3x3 formation. Every square is also divided into nine grids. Now the programme fills numbers into some grids and the player has to add the rest. In every square, vertical row and horizontal row every number of 1-9 has to be there exactly one time. This variant features help functions for beginners, a save feature, different difficulty levels, a "boss key" to minimize the game and a print function so the player can solve the puzzles without a computer.