GridMew1Check region A
region A has only one remaining candidate: row 1, column 6. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 1. Place one cat, then exclude 11 other cells.Two distant singleton regions supply the first anchors
Original puzzle gm-6-0028
By GridMew · Published 15 October 2026 · Updated 16 October 2026
6 × 6 practice
Read the starting position, follow the deductions, and check the move that is easy to misread.
Puzzle board · starting state
How to approach this board
Coordinates such as r2c3 mean row 2, column 3. Count rows from the top and columns from the left.
With no givens, inspect A at the top-right and E near the lower centre. Both are one-cell regions. Filling them establishes enough row and column information to begin the rest of the route.
6×6 · 0 fixed cats · 6 explained deductions. Region sizes: A: 1 · B: 6 · C: 11 · D: 13 · E: 1 · F: 4.
A deduction worth checking
Region F is reduced to r6c1 after the two singleton cats. It excludes the rest of column 1, shifting the remaining work toward the right half.
A move to double-check · r4c4
The cat at r5c3 excludes r4c4 by corner contact. A forced singleton must still update its neighbors, not only its own region.
Green marks the cell being discussed, not a cat to place. This is the position before step 2; compare the deduction below.
Read the starting board as text
Each line is one row, left to right. Matching letters belong to the same connected region.
C C B B D A C C B B D D C C C B D D C C C B D D C F E D D D F F F D D D
Fixed cats: none. One cat is required in each row, column and region.
Step-by-step walkthrough
2Check region E
region E has only one remaining candidate: row 5, column 3. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 2. Place one cat, then exclude 12 other cells.3Check region F
region F has only one remaining candidate: row 6, column 1. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 3. Place one cat, then exclude 4 other cells.4Check row 4
row 4 has only one remaining candidate: row 4, column 5. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 4. Place one cat, then exclude 2 other cells.5Check row 3
row 3 has only one remaining candidate: row 3, column 2. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 5. Place one cat, then exclude 1 other cells.6Check row 2
row 2 has only one remaining candidate: row 2, column 4. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 6. Place one cat, then exclude 0 other cells.Show solution · reveals all cat positions
The final cats satisfy every row, column and region quota, with no edge or corner contact.
Cat positions: r1c6, r2c4, r3c2, r4c5, r5c3, r6c1.
Try another puzzle
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Read this walkthrough →Two singleton regions set up a vertical lock
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