Sudoku Variants Series (421) - Shifter Dots
(Published on 25. April 2025, 12:00 by Richard)
Logic solvable
Shifter Dots
Inspiration for this type comes from gUBBLOR.
Solve online in Sudokupad.
Like all of my sudoku variants, this puzzle can be solved by logic alone. Guessing is not required and also no sophisticated solving techniques are necessary; just plain and easy sudoku steps and of course the intrinsic logic this specific variant has to offer. In case you don't find that logic or get stuck, feel free to ask for a hint in the comments below this puzzle and I'll be happy to help you.
Apply classic sudoku rules.
Digts on different sides of a shifter dot must always have either the same parity (even {2,4,6,8}/odd {1,3,7,9}), or the same polarity (high {6,7,8,9}/low {1,2,3,4}). Never neither, never both. The digit 5 may not appear next to a shifter dot. Not all shifter dots are necessarily given.
Allowed: 8,4 (both even; one high, one low), 8,9 (both high; one odd, one even).
Not allowed: 7,2 or 2,4.
Solution code: Column 1.
Comments
on 23. June 2025, 07:19 by Macarena
Explendorous! Kinda weird at first glance, but very, very elegant. Surprised me a lot, on a good way. One of my favorites. Incredible idea.
on 9. May 2025, 00:19 by dzamie
I confused myself for so long by thinking that there were 4 kinds of polarity here, rather than just 2.
The coloring trick was very handy, to keep track of which rows, columns, and boxes had how many of each!
on 28. April 2025, 10:50 by Johan
Started this puzzle a few times and each time I got stuck. The solution came by thinking less and looking more at what is not possible. After that I had solved it fairly quickly.
Thanks for the nice puzzle.
on 25. April 2025, 18:00 by Franjo
Oh! I tried to do this in the morning - and failed in desperation. I was sure I broke the puzzle… But now I got it! And loved how the ruleset works. Thank you very much, Richard, for creating and sharing another beautiful puzzle. And don’t worry about the typo.
on 25. April 2025, 17:27 by firespire
Started with my usual technique of checking every option then got bogged down.
I know 'Sudoku Sleuth' on YouTube explains Shifter Dots with two colours but I've never taken it in.
Found one of his later videos on Shifter dots to learn the skill.
Boy is it simple to just colour and not have to check the relationships.
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Reply: That sounds indeed like an easy way to approach!
Would love to see how that works for this specific puzzle. :)
I hardly watch YouTube channels were puzzles or sudokus are solved; I simply don't have time for that...
on 25. April 2025, 16:44 by gUBBLOR
Very nice puzzle!!
on 25. April 2025, 16:21 by Piatato
Smooth puzzle! I found the variant to be a bit confusing at first, so maybe it was actually good that I got to practice with a couple of false starts :)
on 25. April 2025, 16:10 by Richard
This puzzle was tested with grey dots. Only this morning I found out what color to use for the dots and made the link in Sudokupad app + image in a hurry before work. But hurry is never good.
Now everything shoud work. Once more my sincere apologies... :(
on 25. April 2025, 16:09 by Richard
Fixed typo in the puzzle + solve link.
on 25. April 2025, 16:03 by Richard
My sincere apologies, there is a typo in the puzzle. Will be fixed!
on 25. April 2025, 15:58 by Piff
I don't know what i'm doing wrong, i restarted the puzzle 3 times and keep running into unsolvable contradictions :(
Edit: thank you for fixing, very nice puzzle :)
