Paired Clues
Two clues that share neighbours, or whose neighbours see each other, often leave only one arrangement they both allow.
How it works
- 1These two walls sit diagonally and share two cells — the pair between them, both marked; the three crosses are all Crowding a Clue could take from the 3.
- 2The 1 allows at most one bulb in that shared pair, so the 3 can count on at most one of them too.
- 3But the 3 still needs three bulbs, so it must take both of its other neighbours: the cell to its left and the one below it are bulbs.
- 4And the 1's single bulb is now certain to come from the shared pair, so the 1's own two remaining neighbours are empty. Neither wall could have told you any of this on its own.
- Cells that establish the pattern
- Bulb this technique places
- Cell this technique rules out