Find the Cat #240: 10x10 Grid Puzzle (Hard)
hardTap a square: ✕ (ruled out) → 🐱 (cat) → clear
Every row, every column and every color region needs exactly one cat -- but no two cats may touch, not even diagonally. This puzzle is a 10x10 grid with 10 colored regions.
- One cat in every row and every column.
- One cat in every color region.
- Cats can’t touch — not even diagonally.
Step-by-step solution
Squares are written as R<row>C<column>, counting from the top-left. Cross out the squares listed, and place a cat wherever a step says so.
- The Red region has only one open square left: R1C1. Put a cat there.
- Wherever the cat in the Green region ends up, it rules out R3C9. Cross that square out.
- Wherever the cat in the Teal region ends up, it rules out R3C4. Cross that square out.
- Wherever the cat in the Pink region ends up, it rules out R4C7. Cross that square out.
- The Green and Teal regions can only use rows 2 and 3, so rows 2 and 3 are already spoken for. Cross out R2C6, R2C7, R3C3, R3C5, R3C6, R3C7 and 1 more.
- The Pink region has only one open square left: R4C9. Put a cat there.
- Row 3 has only one open square left: R3C2. Put a cat there.
- The Grey region has only one open square left: R5C3. Put a cat there.
- The Purple region has only one open square left: R9C4. Put a cat there.
- Wherever the cat in the Orange region ends up, it rules out R6C6. Cross that square out.
- Wherever the cat in the Yellow region ends up, it rules out R2C8, R7C7 and R10C8. Cross those squares out.
- The Green region has only one open square left: R2C10. Put a cat there.
- Wherever the cat in the Blue region ends up, it rules out R6C8 and R7C6. Cross those squares out.
- Wherever the cat in the Yellow region ends up, it rules out R8C7. Cross that square out.
- The Brown region has only one open square left: R10C7. Put a cat there.
- The Blue region has only one open square left: R6C5. Put a cat there.
- The Orange region has only one open square left: R8C6. Put a cat there.
- The Yellow region has only one open square left: R7C8. Put a cat there.
About this puzzle
Where to start: the Red region is a single square, so its cat is already decided. Its 10 color regions range from 1 square (Red) to 19 squares. It can be solved in 18 deduction steps using grouped row/column/region deductions.
Look for a color that sits entirely inside one row or one column. Its cat must be in that line, so every other square in that line can be crossed out.
Stuck? Open the step-by-step solution below -- each step names the row, column or color involved, so you can use it as a hint and then finish the puzzle yourself.