LEVEL 6
Skyscraper
Two strong-link rows share one aligned endpoint and expose a roof elimination.
How to find it
- Find two rows where a candidate appears exactly twice.
- Align one endpoint in the same column.
- Remove the candidate from cells seeing both unaligned endpoints.
Candidate-map demonstration
The violet cells mark the pattern and the gold cell marks the resulting placement or elimination. Treat this compact map as orientation; use the verified full puzzle below to practise the actual deduction.
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Common mistakes
- Using cells that do not share the required row, column, box or peer relationship.
- Removing a candidate before confirming every occurrence in the pattern.
- Confusing a possible pattern with a completed logical proof.
VERIFIED PRACTICE
Skyscraper training
Loading a mathematically verified puzzle state…