Normal Quattroquadri rules apply. Place the digits 1 through 9 in each empty cell. Digits must not repeat within the same row, column, or box.
Kropki: Digits separated by a white dot are consecutive;
Digits separated by a black dot have a 1:2 ratio; digits not separated by a dot are neither consecutive or in a 1:2 ratio
Best Friends: if the digit in a cell is friendly (it shares a number with the cell's row, column, or box) it must be friendly in more than one way (eg. The digit 2 could appear in r2c2 or r1c1 but not r1c2)
Solution code: column 4, top to bottom
on 15. August 2025, 04:33 by corrie
Solving this definitely felt like sculpting by subtraction, very nicely done!
on 9. August 2025, 07:57 by Treme
Lovely stuff :) thanks
on 5. August 2025, 15:11 by Toxter
Very fresh and weird logic!
on 4. August 2025, 22:14 by PancakePie
Whoa! Fumbled my way through, but it was a joy!
on 3. August 2025, 17:28 by MathGuy_12
Lovely miracle puzzle! Really cool interactions
on 3. August 2025, 12:49 by Franjo
Thank you very much for creating and sharing this lovely puzzle.
on 3. August 2025, 08:28 by Fra314
Neat! A really cool puzzle!
on 2. August 2025, 18:01 by Qodec
Remarkable how this solves.
on 2. August 2025, 15:32 by jwsinclair
Enjoyed this a lot :)
Difficulty: | ![]() |
Rating: | 88 % |
Solved: | 59 times |
Observed: | 3 times |
ID: | 000OIC |
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