Jigsaw Killer Sudoku Rule.
Irregular Sudoku + Killer sudoku
Irregular Sudoku
Place a digit from 1 to 9 in each empty cell so that each digit appears exactly once in each row, column and outlined region. Each outlined region is marked by thick borders.
Rules of 9x9 Killer Sudoku Puzzle
Place a digit from 1 to 9 into each of the empty cells so that each digit appears exactly once in each row, column, and outlined 3x3 box. The sum of digits in cells inside every cage must equal the total given for the cage at the upper left cell. Digits do not repeat inside a cage.
Killer Sudoku is a variation of Sudoku that adds an extra challenge by using cages to restrict the placement of numbers.
The basic rules of Killer Sudoku are the same as standard Sudoku:
Each row, column, and 3x3 block must contain the numbers 1-9 exactly once.
The new rule in Killer Sudoku is that there are cages in the puzzle. Each cage has a number in its corner that tells you the sum of the numbers in that cage.
To solve a Killer Sudoku puzzle, you need to fill in the grid so that the numbers in each row, column, and 3x3 block add up to the correct number, and the numbers in each cage add up to the number in the cage's corner.