Whispers in the mist
(Published on 2. February 2025, 04:48 by pdyxs)
Here's another entry in my "Experimental fog" series. Here I'm continuing to explore how fog clearance could itself be information, this time combining it with yin-yang rules.
Rules
Sudoku: Fill the grid with digits 1 to 9, so that each digit occurs exactly once in every row, every column and every 3x3 box.
Yin Yang Fog: The grid is covered in fog. Once the puzzle is completed, any unshaded cells will be revealed, and shaded cells will still be covered in fog. All shaded cells are orthogonally connected, all unshaded cells are orthogonally connected and no 2x2 region is entirely shaded or entirely unshaded.
Clearing Fog: Entering a correct digit in an unshaded cell will clear the fog:
- in that cell;
- in seen cells - any unshaded cells that can be seen from that cell in an orthogonal direction (with shaded cells blocking vision); and
- around corners - any unshaded cells that are orthogonally connected to a seen cell
Unshaded Whispers: Any two orthogonally connected unshaded cells must have a difference of at least 5.
Kropki: A white dot separates digits which are consecutive.
Given Digits: White digits are given, but have not been entered into the grid.
More Experimental Fog Puzzles
Solution code: Code will be revealed in SudokuPad when the puzzle is completed
Comments
on 8. February 2025, 23:34 by Kermit
Great use of fog; I was stumped in a couple of places but felt perfectly fair in retrospect.
on 4. February 2025, 13:29 by davidemsa
Very interesting use of fog in a new way. And it made for a reasonably approachable yin yang puzzle, which isn't common.
on 3. February 2025, 20:08 by azsuth
yin yang with the fog was such an incredible surprise. this is rated criminally low.
on 3. February 2025, 14:40 by Flinty
Beautiful puzzle. Well done.
on 3. February 2025, 10:53 by TheNineElements
Solve Time: 32:31
I rated this 2/5 difficulty.
Wow, great puzzle! Really liked the logic around the 'revealed/cleared' cells for the yin yang logic! The ruleset was totally new to me and a very creative & fun idea.
This puzzle was a very nice balance of approachability and difficulty/novelty, and the solve path was very fun and smooth. I think the early-midgame logic around Box 2/3 was my favorite part of the solve - which was a beautiful use of all of the rules together.
The difficulty felt very consistent around 2*, although it did take me a bit longer than usual for the difficulty rating. Part of this is due to my inexperience with yin yang variants, and partly because I took a long break in the middle of the solve. The logic was definitely approachable and consistent throughout - and this puzzle should be approachable [enough] for novice-intermediate solvers with a bit of experience with each of the rules on their own. None of the steps were particularly complex on their own, but it does rely on having a basic understanding of the "big ideas" in yin-yang, German whispers, and white kropki dots, so a true beginner may struggle to solve this.
The hardest aspect of this puzzle, in my opinion, was understanding how the yin-yang fog clearing rules actually worked, and it required several readings of the rule to understand what 'around corners' met. With that being said, I think the rule is very well-stated/phrased, and I think you did a great job of concisely stating a rule which was totally new to me.
The puzzle unfortunately seems a bit underrated; it really felt like a top-tier puzzle and deserves a higher approval rating IMO. I thought this was an excellent puzzle and a very cool ruleset! Thanks for sharing!
on 3. February 2025, 09:48 by Snookerfan
Fun puzzle with a lovely use of the dynamic fog. Thank you!
on 2. February 2025, 20:43 by Visumation
Very nice. Thanks
on 2. February 2025, 14:25 by therealsillypenguin
Wonderful puzzle, and very creative fog rules!
on 2. February 2025, 10:50 by nunc
Very clean puzzle, loved it. Thanks a lot for sharing!
on 2. February 2025, 09:54 by Big Tiger
Easy enough to be enjoyable just before bed, challenging enough to make it worthwhile.
on 2. February 2025, 05:44 by Nylimb
Very nice use of dynamic fog. Thanks.
