The Killer Sudoku it's a tool at your disposition to resolve the sudoku you want to.

The Killer Sudoku counts with two modes if you want to use it and they are:

-One: the normal, that indicates you the boxes with the fixed numbers and resolve them inmediately.

-two: The killer, in which the total sum appears.

Another of the characteristics this tool offers to you is that you could dispose of differents velocities when you want to resolve the sudoku.