GridMewA small step toward a better solve.
Start with the rules. Build up to a full puzzle.
Learn at your own pace with clear explanations and original examples. Each lesson builds a practical skill you can use right away.
Featured lesson
The rules, in three minutes
One cat per row, column and region. No edge or corner contact. Clear examples and a real first step.
Start learningLearning path
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1The rules
Learn the row, column, region and no-touch rules, and make your first moves.
2Candidate marks
Use × as a record of exclusions, and distinguish notes from fixed facts.
3The no-touch rule
Understand edge contact, corner contact and distant diagonal placements.
Spot the next move
4Single candidates
Find forced cats by checking the remaining cells in a row, column or region.
5Row and column scans
Cross-check constraints instead of solving one region in isolation.
6Region-line locks
Exclude candidates using the intersection of a region and a row or column.
7Narrow regions
Use region shape to focus attention while checking all row and column constraints.
Put it together
Worked puzzles
105×5 walkthrough
Follow an original 5×5 board from fixed cats to a complete verified arrangement.
116×6 walkthrough
Follow an original 6×6 board from fixed cats to a complete verified arrangement.
128×8 walkthrough
Follow an original 8×8 board from fixed cats to a complete verified arrangement.