6x6 Doppelgänger Somedoku
(Published on 9. December 2025, 01:14 by laquartetfan)
Any feedback is appreciated!
After receiving some feedback, I've rewrittten the puzzle rules to improve clarity, changed cosmetic aspects of the puzzle, and added a solution check. But the puzzle and its logic remains unchanged.
Rules:
DOPPELGANGER SOMEDOKU:
The puzzle consists of a 7 by 7 grid missing the R7C7 cell.
For n between 1 and 6, row n contains exactly one 0 and n distinct digits from 1-6, repeating digits as necessary.
For n between 1 and 6, column n contains exactly one 0 and n distinct digits from 1-6, repeating digits as necessary.
Row 7 consists of a complete set of the digits 1-6. Column 7 consists of a complete set of the digits 1-6.
For each 0 in the puzzle, the digit in row 7 of its column is different from the digit in column 7 of its row.
ARROWS: Digits along an arrow sum to the digit in that arrow's circle.
XV-SUMS: Cells separated by a V sum to 5. Cells separated by an X sum to 10. Not all Vs or Xs are necessarily given.
ODD-EVEN: A digit in a gray circle must be odd.
If the rules seem confusing, this example of what a completed 4x4 grid might look like may be helpful.
Solution code: Column 3 and the digit in the cell below the column (7 digits total)
Comments
on 12. January 2026, 13:45 by wullemuus
What a pleasure that so many Doppelgänger puzzles are popping up in these days. A very creative combination of these rulesets- the example made all very clear (for I haven't known Somedoku puzzles before). Quite an easy apertizer ;-)
on 12. January 2026, 01:59 by Kafkapharnaum
Very fun! I attempted your most recent puzzle before that one, seeing how it didn't seem to be getting any solves, but I can see why -- anyway, as my very first 'Someduku', I just couldn't solve it, but I guess the time I spent thinking about it paid off somewhat, as I just blazed through this one as my first actual Somedoku solve (still voted 3/5 though, as I like to think of first time solvers).
The ambiguous quality circles in House are just too floaty for me still, so I will have to get back to it at some other time, but I enjoyed this one! Oh, and thank you for the shout out of course :D
laquartetfan: Thanks so much! Familiarity with somedoku logic is definitely more helpful than familiarity with doppelganger logic for this ruleset, and Housing Bubble isn't a particularly approachable puzzle in any case. Thanks for giving it a shot, and for giving this puzzle a solve!
on 10. January 2026, 16:07 by laquartetfan
Slightly revised rules for formatting.
on 11. December 2025, 07:49 by bodemeister
Nice little puzzle! Fun to step out of my comfort zone and have digit(s) that are actually missing in rows/column. Thanks for the puzzle!
laquartetfan: Thanks so much! You have some great doppelganger puzzles, so that means a lot!
on 10. December 2025, 16:03 by laquartetfan
I edited the image of the 4x4 example puzzle in accordance with the cosmetic changes made to the main puzzle.
on 10. December 2025, 15:57 by laquartetfan
In response to feedback, I rewrote the puzzle rules to improve clarity, changed cosmetic aspects of the puzzle, and added a solution check. But the puzzle and its logic remains unchanged.
on 10. December 2025, 06:31 by Aronana
Very fun puzzle, with a unique ruleset! Kinda nitpicky but it would be nice if there was a completion checker or smthn on the sudoku pad link. I look forward to trying more of yours!
laquartetfan: Thanks so much! Your comment inspired me to figure out how to add solution check to my puzzles, so thanks for that too!
on 9. December 2025, 22:20 by marcmees
nice puzzle. Thanks
on 9. December 2025, 18:36 by gfoot
Interesting combination - it took me a while to understand the rules as what "replaces" means is a weird concept when combining with somedoku. I feel like there must be a clearer way to explain the rules but I'm not sure what it is!
laquartetfan: Thanks for the feedback! I'm working on a full size doppelganger somedoku puzzle, and when I post that I'll try explaining the rules differently.
on 9. December 2025, 15:57 by flutchman
Nice puzzle indeed.
Great debut.
I don't think it's easy though.
This was my first somedoku and also my first doppelgänger: takes a bit of effort to understand what's going on.
laquartetfan: Thanks so much! I wasn't sure what difficulty to rate it, and it definitely helps to be familiar with doppelganger and somedoku logic.
on 9. December 2025, 14:23 by Thuna
It's a nice puzzle. It's fun to work through once you're in the right mindset as to how you are supposed to approach it.
I think the description of 0 "replacing" digits is confusing, though, because of the lack of correlation between what digit is not in the column/row and what digit the 0 "replaces". Not that I was able to come up with a better way to explain it.
laquartetfan: Thank you! I'm working on a full size doppelganger somedoku puzzle, and when I post that I'll try explaining the rules differently.
on 9. December 2025, 02:00 by laquartetfan
I fixed the images and links from my initial upload of the puzzle.
