Killer at large in the fog: #2
(Published on 28. January 2025, 14:29 by Fenners)
The Zodiac is back for a second time! Can you crack the code and decipher the letter?
...........................................................................................
Puzzle: Killer at large in the fog: #2
Rules:
The Zodiac has posted another letter to me detective. This one feels larger than the last, I hope that means there is more information this time...
Listen carefully to the rules the Zodiac sent me and do not forget them, we don't have much time!
The 9x9 Sudoku grid is surrounded by a 1 cell wide outer ring. Within the 9x9 Sudoku grid, normal 9x9 sudoku rules apply. On the outer ring, digits cannot repeat and are only placed in yellow shaded cells. If a german whisper enters into a cell in the outer ring, then it is a yellow cell.
Smudge: Again the letter is smudged, placing correct digits will remove the smudge marks around that cell.
German Whispers: Adjacent digits on a green line must differ by at least 5.
Numbered rooms: A Digit X on the outer ring either sees a full row or a full column. The digit X must be placed in the Nth position (read left to right, or top to bottom) of whichever it sees fully, where N is the first digit X sees of that row or column.
Get to work detective, and good luck!
Solution code: Row 9 of the 9x9 Sudoku grid:
Comments
on 7. February 2025, 17:28 by Friedhelm
Well done Fenners! Thanks! Very logical.
on 1. February 2025, 14:10 by fishsaltyak
Really wish that conflict checking worked properly.
on 1. February 2025, 06:00 by TheNineElements
Solve Time: 24:07
I rated this 2/5 difficulty.
Excellent approachable sudoku puzzle! I think it is very underrated (based on the user submitted ratings). Having now read the comments, it may be due to the confusion about German whispers traveling through/in fog on the outer ring, but with the current phrasing of the rules, I think this puzzle deserves a much higher rating. Definitely a top-tier puzzle in the 2* difficulty class.
The whole puzzle was very fun to solve, and the 'numbered rooms' rule is a variant that I've only seen a handful of times, which was a nice change of pace. The clues were very well placed within the fog, and they made for an fun solve path. I really enjoyed how the solve went so smoothly and how the logic difficulty was very consistent throughout the solve.
I did get stuck for around 5 minutes towards the beginning because I forgot that the 'Nth' cell position (from the numbered rooms rule) was read left-to-right, and not the distance from the right-side clue. This is definitely my own mistake, and I should have read the rules more thoroughly. Other than that, everything was straightforward and engaging.
I've been enjoying modified-grid FoW sudoku puzzles (i.e., FoW variants where the user places the cells outside the normal 9x9 sudoku), and this is an excellent example that is more approachable than the other ones I've seen/solved so far.
Thanks for sharing!
on 31. January 2025, 20:02 by dzamie
This puzzle showed me how much I tend to rely on sudokupad auto-marking pencilmarks that conflict with full digits.
Very fun, though! Took me a bit to get used to when a yellow cell showed up on column or row 10, since I'm used to stuff being relative to the side it's written on, rather than absolute r/c numbers.
on 29. January 2025, 03:22 by SanFranSam
I make so many mistakes along the way that i don't know if i should even submit the solution code. ¯_(ツ)_/¯
on 29. January 2025, 01:36 by Fenners
Added a line to the rules
on 29. January 2025, 01:14 by VitP
this is a great puzzle.
HOWEVER, if it is CRITICAL to read the rules EXACTLY, then you should be aware that there is an ERROR in the rules.
so,
a) can we use the fact that there is a STATED difficulty rating? no, because that is frequently wrong.
b) can we use the fact that a specific ASSUMPTION is required in order to make reasonable progress? no, because that is sometimes broken on this site, see above.
c) one needs to ASSUME that r0c6 is a YELLOW cell in order to reasonably make progress at some point, and with THESE rules, the assumption is invalid.
Fenners: Thanks for the feedback. I've added the line "If a german whisper enters into a cell in the outer ring then it is a yellow cell. Does that clear the assumptions well enough?
on 28. January 2025, 22:02 by mvondras
There were some issues with conflict checking. GREAT PUZZLE
on 28. January 2025, 18:15 by saturnic
genial!
on 28. January 2025, 17:55 by Adrian71
Nice puzzle, thanks!
on 28. January 2025, 17:52 by PuzzlePatzer
Very nice puzzle! I thought the numbered room explanation was too verbose until I found out that it was absolutely necessary :). I might have not understood the answer :) but I enjoyed the puzzle. Thank you for sharing.
on 28. January 2025, 17:24 by NEMESIS
Wasted time because I overlooked right direction:( nice puzzle
on 28. January 2025, 16:28 by Fenners
Changed to 2*
on 28. January 2025, 16:13 by brightonsimon
Very enjoyable! Somewhat trickier than a 1* for me but got there eventually. Be sure to read the rules properly and count your numbered rooms in the right direction :-)
on 28. January 2025, 15:58 by anyeyeball
Enjoyable puzzle! Thank you, Fenners.
