♛ Queens
← PuzzlesPlace one queen in every colored region — no two queens may share a row, column, or diagonal.
Left-click cycles empty → ✕ → ♛ | Right-click places/removes ♛ | Toggle switches first-tap between ✕ and ♛
How to play Queens
- One queen per region: every colored area must contain exactly one ♛.
- One queen per row and column: no two queens may share the same row or column.
- No diagonal contact: queens cannot touch each other, even diagonally.
- No guessing required: every puzzle is solvable by logic alone. If you're stuck, look for a region, row, or column where only one cell remains valid.
Left-click marks a cell as "not a queen" (✕). Left-click again to promote to ♛. Right-click goes straight to ♛. Use the mode toggle to swap which action comes first — useful on mobile.
Strategies & solving tips
A region with only 2–3 cells gives you the fewest options. Try placing a queen there first and see what it rules out everywhere else.
After placing a queen, mark every cell in the same row, column, region, and the 8 surrounding diagonal cells with ✕. Keeping the board clean prevents mistakes.
If a row, column, or colored region has only one un-marked cell left, that cell must contain the queen. Work through all rows, columns, and regions every time you place a queen — cascades are common.
If all remaining valid cells in a region lie in a single row (or column), the queen for that region will occupy that row (or column). You can therefore mark every other cell in that row (or column) as ✕, even if they belong to a different region.
The reverse also holds: if all un-marked cells in a row (or column) belong to the same region, the queen for that region must be in that row (or column). Mark the rest of that region ✕.
When two regions each have their valid cells in the same two rows, the queens for those regions must occupy those two rows — so every other region's cells in those rows can be marked ✕. The same logic applies to columns.
Corner cells only have 3 neighbours; edge cells have 5. Queens placed near a corner eliminate fewer options than queens in the middle, so edge placements can be easier to reason about when you're starting out.
If you reach a contradiction (a row, column, or region with no valid cell left), undo your last placement and try the next candidate. A correct puzzle always has a logical path that requires zero guessing.