Sudoku with the numbers taken away and sums put in their place. Dotted cages tell you what the squares inside them add up to, and the rest is up to you.
A new puzzle every day at five difficulties, each one with a single solution.
The usual Sudoku rules apply: one to nine once in every row, column and three by three box.
On top of that, each dotted cage has a total, and the numbers inside it add up to exactly that. Numbers never repeat inside a cage either.
Small cages are the way in. A two square cage totalling four can only be one and three, and a three square cage totalling six can only be one, two and three.
The other reliable trick is counting. Every row, column and box totals forty five, so a cage that spills slightly outside a box tells you what the leftover squares must add up to.
No. A cage behaves like a small unit of its own, so every number in it is different as well as adding up to the total.
With the smallest cages. Totals like three, four, six and seven have only one combination, and those combinations spread through the grid quickly.
Every row, column and box adds up to forty five. If cages cover a box except for one square, that square is forty five minus the cage totals.
Different rather than harder. You do more arithmetic and less scanning, and the easy difficulties here are gentler than they look.
Killer Sudoku crossbreeds Sudoku with Kakuro, and the result is a puzzle where the first few moves feel impossible and then the grid opens all at once.
The combinations are worth learning. There are only so many ways to make fifteen out of two squares, and knowing them turns a long puzzle into a short one.
Every puzzle here is generated fresh and checked for a single solution, so nothing ever comes down to a guess.