Line Weave: close a completed run without trapping the next
Identify a completed three-square run in an eight-square line, place its necessary empty separators and recognise when a similar-looking fragment is still ambiguous.
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 completed run creates empty information
In Line Weave, a run is a consecutive group of filled squares. Once you know which clue a group satisfies and know that its length is complete, the squares immediately before and after it must be empty, where those squares exist. Otherwise the group would become longer or touch the neighbouring run without a separating gap.
That deduction can be as useful as filling a square. A cross records the empty conclusion for later inspection. It is not a penalty mark, and the game does not decide whether each individual cross is correct when you place it. You still need to explain why the marked square cannot belong to a filled run.
Inspect an eight-square line with clues 3, 1
Number the squares 1 through 8 and suppose squares 3, 4 and 5 are already known filled. With clues 3, 1, those three consecutive squares must form the first run. They cannot be the single-square second run, and extending their group would exceed the first clue. The run therefore occupies exactly squares 3 through 5.
Squares 1 and 2 are empty because the first run has already begun at square 3. Square 6 is the mandatory separator. The remaining single filled square can occupy either square 7 or square 8. Written with 1 for filled and 0 for empty, the two compatible rows are 00111010 and 00111001.
Leave the unresolved choice unresolved
The line alone does not choose between those last two patterns. Marking both squares 7 and 8 filled would join them into a run of two, contradicting the final clue of 1. Crossing both would remove the required final run. A column constraint must settle which one is filled and which is empty.
For example, if the column through square 7 is already proved empty at this row, then square 8 must be the final filled square. The word proved matters: an old cross entered during an uncertain experiment is not new evidence. Recheck its column reasoning before using it to force another mark.
Do not close an unidentified fragment too soon
A group of two filled squares is more ambiguous in a line with clues 2, 3. It might complete the first run, or it might be part of the later three-square run. Crossing both ends without identifying the group can accidentally prevent that second possibility. Run length alone is not enough when more than one clue can explain the visible fragment.
Read the clues in order, account for empty separators and compare all placements still permitted by known marks. Use Mark empty or the X key for a justified gap, and Undo to reverse a mark that relied on a mistaken identification. The helpful habit is to close a run after proving its role, rather than treating every neat-looking group as a completed clue. Two possible patterns can be a useful result even before a line is finished.
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