Cool Runnings (Chaos Construction)
(Published on 4. September 2026, 11:09 by Mad-Tyas)
Sudoku on:
SudokuPad
Rules:
Chaos Construction: The grid has to be divided into nine regions of orthogonally connected cells. Each row, column and region has to contain the digits 1-9 once each.
Runs: Each uninterrupted extent of cells from a region in a row or column is called a Run. Single-cell Runs are possible. The sum of the digits in a Run is called Run Sum.
Clues: If a small number is given in the bottom-right corner of a cell, it gives the result of adding up the Run Sums of the vertical Run and the horizontal Run this cell is part of.
Have fun solving!
Example: This is an example picture to clarify Runs and Run Sums. Some Runs are indicated by arrows next to them and the respective Run Sum is given by a red number.
Solution code: The 9 digits from column 7 (top-to-bottom) separated by (+) for borders between regions
Comments
on 12. October 2026, 22:09 by peacherwu2
Like someone commented, things are pushed to extremes. If you spot it, you are on the roll.
on 4. October 2026, 13:35 by Flinty
Excellent setting, squeezing so much out of those clues. :)
on 24. September 2026, 10:04 by Saltensity
When I first saw this released, I attempted it and got stuck pretty quickly, so I had to give up. I've came back to give the ruleset another try and persevered through it 2 hours, and managed to solve it. The rules are simple to understand but the puzzle is very difficult, so kudos to you for being able to set this puzzle! Thank you, Mad-Tyas :D
on 21. September 2026, 22:54 by War
That was amazing. I really don't know how you do it.
on 17. September 2026, 07:14 by Crusader175
Very nice!
on 6. September 2026, 23:00 by emoney1374
Great puzzle!
on 6. September 2026, 13:52 by Firebird
Remarkable puzzle, brilliant setting!
on 6. September 2026, 12:49 by karlmortenlunna
Brilliant puzzle!
on 5. September 2026, 15:40 by Mad-Tyas
Included example picture for clarification
on 4. September 2026, 21:39 by wuc
Great cc puzzle. Tough 4*. Lots of cool deduction in the region findings. Brilliant setting thx.
on 4. September 2026, 21:37 by Mad-Tyas
German translation fixed
on 4. September 2026, 18:54 by Qodec
What a treat. Better than ice cream!
on 4. September 2026, 18:08 by Franjo
Thank you very much for creating and sharing this absolutely fantastic CC-puzzle. Not easy, but so satisfying!
on 4. September 2026, 14:54 by Myxo
Lovely!
on 4. September 2026, 14:46 by Snookerfan
Brilliant puzzle! A little twist on familiar rules, leading to a bunch of fresh logic. Very hard and very entertaining, thanks!
on 4. September 2026, 14:40 by marcmees
Not simple at all, apart from the rule set. :-) Very nice. Thanks.
on 4. September 2026, 14:34 by Chaossudokusplease
Very fun, very interesting chaos constraint. Definitely took me a few false starts to get the hang of the sums and then I still had to be very careful double checking my work!
