Back to the technique guide · This position comes from a real puzzle. Apply the highlighted hint to continue solving. Use "Undo" to reverse your last change.

Technique example: Naked quad

	C1	C2	C3	C4	C5	C6	C7	C8	C9
R1
R2
R3
R4
R5
R6
R7
R8
R9

Use the arrow keys to move, 1-9 to enter a digit and Backspace or Delete to clear a cell. To add or remove a candidate, press C and then 1-9.

Show candidates

(Difficulty: Expert)

This example comes from puzzle number 37025 and includes the candidate removals made in earlier steps. Play this puzzle from the start