Queens puzzle strategy: find your next move without guessing

By Puzzledoku · Published October 9, 2026 · Last updated October 9, 2026

When a Queens board looks empty of clues, the next move is often an elimination, not a placement. The useful question is: which cells fail under every possible position of a required puppy?

A repeatable scanning order

This guide assumes you know the three Queens rules: one puppy in every row, column and color region, and no touching, including diagonally. Here is a routine for deciding which technique to try next.

1. Clear confirmed placements. Cross out the rest of the puppy’s row, column, color and neighboring cells. Auto X can do this for you. Leaving a forbidden cell open makes later candidate counts misleading.
2. Count remaining candidates. Check every row, column and color for a single open cell. Count the cells that remain possible, rather than the original size of the region.
3. Look for a line reservation. If a color can only use one row or column, that line belongs to it. Eliminate the other colors in the line before choosing the actual cell.
4. Compare all options of a small group. For each nearby cell, ask whether every candidate would rule it out. One option may share its column, another may touch it.
5. Count groups against lines. Two colors restricted to the same two rows fill those rows. Three colors restricted to three columns work the same way. Count distinct rows or columns, not cells.

After any elimination, restart at the top of the routine near the changed cells. A small deletion may create a single elsewhere. Follow the consequences of one move instead of repeatedly scanning without updating your candidate counts.

Worked opening: October 9, 2026

Open this exact daily board alongside the guide. This sequence is checked against its actual regions and solver. It is an opening walkthrough; the dated page has a separate folded full solution.

Start with an unmarked board. Rows run from top to bottom and columns from left to right, starting at 1. Apply these steps in order; none places a puppy or reveals the full answer.

1. Reserve row 5

   Candidates: row 5, column 7; row 5, column 8.

   The two-cell color region at the right edge lies entirely in row 5. Its puppy must go in column 7 or 8 of that row. Therefore row 5, columns 1–6 cannot hold a puppy, even though neither candidate has been chosen.

   Cross out: row 5, column 1; row 5, column 2; row 5, column 3; row 5, column 4; row 5, column 5; row 5, column 6.

2. Compare both candidates before placing anything

   Candidates: row 5, column 7; row 5, column 8.

   Row 5 now has only two candidates. If the puppy goes in column 7, the listed cells in column 7 share its column and those in column 8 touch it. If it goes in column 8, the same argument works with the columns swapped. All four cells are forbidden in either case.

   Cross out: row 4, column 7; row 4, column 8; row 6, column 7; row 6, column 8.

3. Use the same test on the top-right region

   Candidates: row 1, column 7; row 1, column 8; row 2, column 7.

   This color can use row 1, column 7; row 1, column 8; or row 2, column 7. Row 1, column 6 shares a row with the first two options and touches the third. Row 2, column 8 touches both row-1 options and shares a row with the third. Both cells are impossible whichever candidate is correct.

   Cross out: row 1, column 6; row 2, column 8.

Now scan the affected rows, columns and colors again. Look for a single remaining cell or another group confined to a line before trying a longer “what if” chain.

The first move uses a shared row. The next two compare candidates that block a cell for different reasons. The method stays the same: identify a group that needs a puppy, list all its remaining positions, and keep only conclusions true for every position.

When the simple moves run out

A contradiction is a proof if you can name the failed rule. Suppose one candidate contains a puppy and carry out the forced eliminations on a scratchpad. If a still-empty row, column or color loses its last candidate, the assumption is impossible. Two forced puppies sharing a line or touching also disprove it.

Do not turn “this looks awkward” into an X. If the chain branches and you cannot complete the proof, leave the cell undecided. Use Hint to inspect a next step, then explain its reason in your own words. A wrong placement consumes a bone; an unproven X can also hide the clue you need.

Practice the deduction, not the coordinates

Try the October 8 opening next. Its first moves reserve columns instead of a row. Before reading the explanation, identify the relevant color and predict which cells it excludes. Then compare your reasoning with the dated walkthrough.

For regular practice, use the 200-level collection. After each placement, name the rule behind your next elimination. That habit transfers to a new board; memorizing an old answer does not.

Put the rules into practice

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