A clue describes runs in order
The clue 3 means one uninterrupted run of three filled squares. A clue of 1, 1 means two single filled squares with at least one empty square between them. Extra empty squares may appear before, after or between runs. You cannot swap the order of unequal runs.
A line containing five squares and the clue 2, 2 has no spare space: two filled squares, one mandatory gap, then two filled squares. By contrast, a single run of three has room to shift. That spare space is what overlap reasoning measures.
A five-square line with clue 3
There are exactly three placements before any crossing information is known. In the table, ■ means filled and · means empty. The positions are numbered from left to right.
| Start | 1 | 2 | 3 | 4 | 5 |
|---|---|---|---|---|---|
| Left | ■ | ■ | ■ | · | · |
| Middle | · | ■ | ■ | ■ | · |
| Right | · | · | ■ | ■ | ■ |
What can you mark immediately?
Reveal the common square
Only position 3 is filled in every placement. Fill it. None of the other positions is always empty, so do not cross any of them yet. Choosing the middle placement would add assumptions that the clue does not justify.
Now suppose the column crossing position 1 proves that square is filled. Only the left placement survives, so positions 2 and 3 are filled and positions 4 and 5 are empty. A single crossing fact can finish the line.
Use empty squares as information
When you have located a complete run, mark the required separating square before searching for the next run. For clue 2, 1, a completed pair cannot extend into a third filled square: that would change the first run’s length.
Cross mode records a square you know is empty. It is different from leaving a square undecided. Switching between Fill and Cross is especially useful on phones, where a right-click is unavailable. If a placement creates a contradiction in a crossing line, use Undo and review the last assumption.
Work back and forth between rows and columns. A finished row gives facts to several columns; those columns can then constrain another row. Looking only at rows misses half the available information.
Use BoomWick’s feedback carefully
Choose a small picture first. The catalogue uses reviewed pictures with unique solutions, but a single line can still have several valid arrangements until you inspect its crossings. A unique overall solution does not mean every next square is immediately obvious.
Hint reveals a correct mark for one square and counts as assistance. It does not explain the deduction, so pause afterwards and ask which row or column now has fewer possibilities. The game recognises the finished picture from its filled squares; crosses are reasoning aids.
The daily picture gives players the same challenge for the UTC date, and your current progress is saved in this browser. To practise another comparison of overlapping groups, read Minesweeper flags and safe neighbours. There, flags represent mines rather than filled picture cells.
Take it to the game
Found a rule that behaves differently or an example that needs explaining? Report the problem with the game and the steps you tried.