How to play Badgers.

1. Every row, column and block holds each number once. The grid size sets the numbers: six by six uses 1 to 6, nine by nine uses 1 to 9. A block is the small rectangle marked by the thicker line, and it holds those same numbers once each too.

2. The dotted cages add up. A cage is the group of cells inside one dotted outline, and the small number in its top left corner is what its cells add up to, with no number repeated inside the cage. Nothing is filled in at the start: the cages are the whole puzzle.

3. Exactly one arrangement fits. Every row, column, block and cage at once. When the last cell is right, the game notices by itself.

Cages carry the other half of the puzzle. A short cage with a low or a high total often has only one possible set of numbers: two cells adding to a small total, or close to the largest one, leave little room to choose from. Once a cage is filled, correct and free of repeats, it goes quiet on the board, a soft cue only, never a judgement while you play.

Every sett opens with steps like these. Hint finds the next one for you, names the rule and the place, and outlines the cage it is reading; press it again to write the number in and explain why. Hints are counted and shown when you finish, never hidden.

• A cage of one cell. Its number is simply its total.
• Only one way to make the total. A short cage with an extreme total, low or high, often allows only one set of numbers.
• The single number left. A cell whose row, column, block and cage between them rule out every number but one.
• Marks already placed. Numbers you have written narrow what still fits; Hint reasons from them the same way it reasons from the cages alone.