Locked In Place
- Killer cages
- Quadruples
The brief
- Normal sudoku rules apply, i.e. each row, column and 3x3 region has to contain the digits from 1 to 9 once each.
- Killer cages: Digits in a cage do not repeat and sum to the clue in the top left.
- Quadruple: Digits in a circle must appear in the four surrounding cells.