Line Weave: find overlap before trying to see a picture
A run of five in a line of eight forces two central squares. Learn why that overlap is reliable, and where a tempting visual guess goes wrong.
Worked examples use the Standard board unless a different size is stated. Hard and Expert may change the board dimensions or amount of information to track.
A clue describes runs, not a drawing
Line Weave gives each row and column an ordered list of filled runs. A row clue of 2, 2 means two filled squares, at least one empty square, then two more filled squares. The runs may have extra empty space before, between or after them. They cannot touch, because touching runs would become one longer run.
Treat the emerging shape as a consequence of those constraints. The patterns here are abstract. Guessing that an unfinished shape ought to be symmetrical can add filled squares that the clues never required. A reliable mark has a line-based explanation that remains true even if the final pattern looks unfamiliar.
Compare the earliest and latest positions
Consider a line of eight squares with the single clue 5. The run could begin in square 1, 2, 3 or 4. If pushed fully left, it covers squares 1 through 5. If pushed fully right, it covers squares 4 through 8. Squares 4 and 5 belong to both extreme placements, and therefore to every placement between them. You can fill those two squares without knowing the run’s exact start.
The other squares remain undecided. Filling square 3 because it sits next to the overlap would go beyond the evidence: the rightmost placement leaves it empty. Record just the forced middle squares, then let their column clues contribute the next piece of information.
Count the separators as real space
A five-square line with clue 2, 2 has no spare space. Its two runs require four filled squares and one mandatory separator, so the only arrangement is filled, filled, empty, filled, filled. The cross in the centre is just as useful as a filled mark because it prevents the runs from accidentally joining.
For longer lines, add every run length and one separator between each neighbouring pair before counting spare squares. Use that space budget to compare the earliest and latest legal placement of each run. An empty mark should follow from the same constraints; it should not be used merely to decorate squares that have not yet been considered.
Carry information between rows and columns
After a forced mark, inspect the crossing line. A filled square may restrict where that line’s run can start, while an empty mark may split its available space. Alternate between the two directions instead of trying to finish one difficult row by itself. A short deduction in a column can unlock the row you were stuck on.
A highlighted clue means that line’s currently filled runs agree with its clue. It is useful feedback, but it does not certify individual squares independently of the crossing lines. Completion requires every row and column to agree together. You may leave unused empty squares unmarked: crosses are reasoning notes, not an extra victory requirement. Use Undo when testing a deduction, and Restart to clear the same pattern without losing the chance to reconsider its clues.
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