Test a crown without guessing

By the Queenwise team · Updated October 9, 2026

A cell belongs to exactly one colored region. To test a crown, choose a region with two remaining candidates, assume a crown in one of those cells and follow only forced consequences. Keep the assumption separate from your established deductions.

If that branch produces two conflicting crowns or leaves an unfinished row, column or region with no candidate, the assumed cell is impossible. Undo the branch and cross out that cell in the original position. If its region had exactly two candidates, the other candidate is now forced.

A branch that stalls without a contradiction proves neither candidate correct. A branch that reaches a complete valid board must still satisfy every rule. Queendom's current hint engine explains singles, line locks and region subsets; it does not promise to perform arbitrary hypothetical chains for you.

• Make one assumption at a time and remember the board position before it.
• Do not count an arbitrary second guess as a forced consequence.
• Undo to the assumption point after the test; avoid leaving tentative marks mixed with proved facts.

When to use it

Testing is a last resort. Use it only after forced crowns, line locks and region groups have all run dry. Pick the region with the fewest candidates — ideally two — so a contradiction immediately forces the other cell.

Keep it honest

• Follow only forced consequences inside the test. Do not stack a second guess on the first.
• Use a different mark style or remember the starting position so you can undo the whole branch.
• A test that leads nowhere proves nothing — return to the original position and look for a different deduction.

Try it on a practice puzzle