Killer Sudoku by Sudoku.com

Sudoku Foundation: The game follows the standard Sudoku rules, where the goal is to fill the 9x9 grid with numbers from 1 to 9, ensuring each row, column, and 3x3 subgrid contains no repeating numbers. Cages & Sums: The twist comes with cages, which are groups of cells that must add up to a specific sum (shown in the upper-left corner of the cage). You must place numbers within each cage that satisfy both the sum requirement and the Sudoku rules. No Repeats: Each row, column, and 3x3 block must contain unique numbers. Within each cage, no number can repeat.