Galactic Union (Killer / Spiral Galaxy / Chaos Construction)
(Published on 23. December 2023, 23:26 by Tacosian)
- Divide the grid into regions, each consisting of nine orthogonally connected cells. Each row, column and region must contain the digits 1 to 9 once each. One region border is given between R4C7 and R5C7.
- The dots in the grid are the centers of 180 degrees rotationally symmetric "galaxies" (non-overlapping sets of orthogonally connected cells). Each half of a galaxy forms a killer cage, summing to the number given on its side of the dot. All cells within a cage must belong to the same region. The two cages formed by a single galaxy must belong to different regions.
SudokuPad link (example): SudokuPad
Penpa+ link (example): Penpa+
The PuzzleSudokuPad link: SudokuPad
Penpa+ link: Penpa+
Solution code: Column 4, from top to bottom. Where there is a region border, type X (uppercase). In the example puzzle, the solution code for column 4 would be 163X452X7.
Comments
on 18. December 2024, 15:16 by DonQuichopp
Wow, what a beautiful puzzle with so many lovely deductions. It took me little under 10 hours to solve and unfortunately I had to use "check solution" a few times, because I knew I screwed up. So it's not a genuine 5* solve, but still I am proud that I managed to get the correct solution :-)
Thanks for this setting! I enjoyed the solve very much.
on 16. December 2024, 09:03 by Camaras
I started to try it but then gave up. It wasn't until I took the time to actually solve the example puzzle that I was able to come back to the real one and figure it out. This was the first five-star puzzle I've solved without using any help whatsoever from the checker! :)
on 15. December 2024, 19:23 by Qodec
Not half as hard as I expected, and some very pretty deductions!
on 15. December 2024, 02:31 by sorryimLate
Very nice! Challenging but not too hard. For me it felt much easier to colour each region with one colour and draw galaxy borders with lines. Thanks!
on 8. March 2024, 16:03 by Fool on Hill
Beautifully done - a sustained challenge with neat things to find at every step until it fills in at the end.
on 7. March 2024, 09:01 by Christounet
Great ! Loved the construction part. Irregular sudoku was the hardest for me because I'm not so good at scanning, but it was still fair. Thanks :)
on 4. March 2024, 13:33 by Silverstep
Brilliant. The break-in itself is beautiful, that goes without saying; but it takes a great mind to make the rest of the puzzle challenging AND still fair at every step.
on 1. January 2024, 01:51 by Agent
Great puzzle, cool geometry and logical flow!
on 29. December 2023, 13:15 by peacherwu2
Incredible geometry. Incredible ruleset.
on 26. December 2023, 04:56 by BHUNTER47
The break-in realization was amazing. After that the region determination went smoothly; but then the irregular sudoku was lovely and complicated as well.
on 25. December 2023, 04:08 by cam
This puzzle was very difficult, but I'm having even more trouble putting into words just how awesome it was to solve. I don't know how you did this--absolute magic.
on 25. December 2023, 00:01 by Jesper
Very nice, thanks!
on 24. December 2023, 20:14 by marcmees
pure magic. thanks.
on 24. December 2023, 17:47 by ONeill
Brilliant, and not too difficult
on 24. December 2023, 16:07 by samuel1997
This is quite a stunning puzzle! The concept in this puzzle is quite clear, but the way to work those regions out is just piece of art!
on 24. December 2023, 13:33 by Lavender Gooms
Loved it. Made it harder for myself than it should have been, but after I realized my mistake it flowed incredibly well.
on 24. December 2023, 12:44 by Snookerfan
Very nice! Lovely break-in. Thank you
