Practise: Naked Pair
This puzzle is picked so that the easy moves run out and exactly the Naked Pair gets you going again. Solve as far as you can — when nothing obvious is left, the pattern is waiting for you.
Skip the obvious cells and start right where the technique is needed.
How to spot it
Scan units for cells with exactly two pencil marks, then look for a second cell in the same unit with the identical pair. The pair must match exactly — {3,9} and {3,9}, not {3,9} and {3,9,5}. Once found, delete both digits from every other cell in that unit.
Put it to use
Where you will meet it
Medium grids are where this move starts to matter: the obvious cells run out and the pattern takes over.
Play MediumStuck on a grid of your own?
Type the position into the solver and it walks the whole solution, naming the technique behind every step — including this one.
Open the solverPrefer paper? Ready-made Medium sets as a PDF.Print puzzles