GridMew1Check region H
region H has only one remaining candidate: row 8, column 4. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 1. Place one cat, then exclude 14 other cells.A bottom singleton sends the solve back upward
Original puzzle gm-8-0056
By GridMew · Published 15 October 2026 · Updated 16 October 2026
8 × 8 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.
The fixed top-left cat fills A. Region H is the single cell r8c4, supplying the next cat at the opposite end. Its effects reduce F to r6c5 before the upper-right regions resolve.
8×8 · 1 fixed cats · 7 explained deductions. Region sizes: A: 10 · B: 11 · C: 2 · D: 11 · E: 15 · F: 2 · G: 12 · H: 1.
A deduction worth checking
C resolves at r3c6 after F is filled. It removes r2c7 by contact and clears other column-6 candidates, opening the row-2 single.
A move to double-check · r2c7
r2c7 is a corner neighbor of r3c6. It is not removed because column 7 is full, so check the exact reason before extending that exclusion elsewhere.
Green marks the cell being discussed, not a cat to place. This is the position before step 3; 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.
A A A A B B B B A A A D D B B B A D D D C C B B A D D D E E B B A D D D E E E E G G G F F E E E G G G G G E E E G G G H G E E E
Fixed cats: row 1, column 1. One cat is required in each row, column and region.
Step-by-step walkthrough
2Check region F
region F has only one remaining candidate: row 6, column 5. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 2. Place one cat, then exclude 11 other cells.3Check region C
region C has only one remaining candidate: row 3, column 6. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 3. Place one cat, then exclude 8 other cells.4Check row 2
row 2 has only one remaining candidate: row 2, column 8. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 4. Place one cat, then exclude 3 other cells.5Check region G
region G has only one remaining candidate: row 7, column 2. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 5. Place one cat, then exclude 3 other cells.6Check row 4
row 4 has only one remaining candidate: row 4, column 3. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 6. Place one cat, then exclude 1 other cells.7Check row 5
row 5 has only one remaining candidate: row 5, column 7. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 7. 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: r1c1, r2c8, r3c6, r4c3, r5c7, r6c5, r7c2, r8c4.
Try another puzzle
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