GridMew1Check row 6
row 6 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 1. Place one cat, then exclude 4 other cells.A bottom-row single reaches a right-edge region
Original puzzle gm-6-0001
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.
The given at r5c4 fills the large E region. The bottom row can then use only r6c1. Filling column 1 helps expose region D’s remaining position on the right edge.
6×6 · 1 fixed cats · 5 explained deductions. Region sizes: A: 3 · B: 9 · C: 6 · D: 3 · E: 11 · F: 4.
A deduction worth checking
D resolves at r4c6. Besides clearing column 6, this cat removes r3c5 by corner contact and leaves row 3 with its eventual single.
A move to double-check · r3c5
r3c5 has a different region and column from r4c6. It still touches the new cat. Check this corner before looking for a more complicated regional deduction.
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 A A B B B C C A B B B C C E B B B F C E E D D F F E E E D F E E E E E
Fixed cats: row 5, column 4. One cat is required in each row, column and region.
Step-by-step walkthrough
2Check region D
region D has only one remaining candidate: row 4, column 6. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 2. Place one cat, then exclude 5 other cells.3Check 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 3. Place one cat, then exclude 3 other cells.4Check row 2
row 2 has only one remaining candidate: row 2, column 5. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 4. Place one cat, then exclude 1 other cells.5Check row 1
row 1 has only one remaining candidate: row 1, column 3. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 5. 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: r1c3, r2c5, r3c2, r4c6, r5c4, r6c1.
Try another puzzle
A narrow central region links two edges
gm-6-0043 · 6×6 · practice
Practice single-candidate placements on another 6×6 board.
Read this walkthrough →The bottom-left pair is not an equal choice
gm-5-0008 · 5×5 · practice
Transfer single-candidate placements to a 5×5 grid; compare how the candidates change.
Read this walkthrough →Two possible cats, one shared exclusion
gm-5-0001 · 5×5 · challenge
Compare this route with shared-neighbor exclusions, and check why that different rule is needed.
Read this walkthrough →