Stay in Your Box
(Published on 2. February 2025, 03:58 by marty_sears)
It was a lot of fun doing this 2nd collab with the ever-talented Justin Vitanza (AKA Puzzle Pusher)
- Normal sudoku rules apply.
- Every box contains an invisible 'index line' whose route must be determined.
- The index lines are all 9 cells long, only move orthogonally (not diagonally), and don't cross any 3x3 box borders. They don't cross themselves, or pass through any black or green spots.
- Each row, column and box contains exactly one hidden diamond, which lies at one end of its index line, and contains its box number. (Boxes are numbered 1-9 in normal reading order from top left to bottom right.)
- The digit in position N along an index line (starting at the end with the diamond) indicates the position along the line where the digit N should be placed. Eg: if the 1st digit (in the diamond) is a 3, then the 3rd digit will be a 1.
- Digits separated by a black spot are in a 1:2 ratio.
- Digits separated by a green spot have a difference of at least 5.
INVISIBLE LINES:
DIAMONDS:
INDEXING:
SPOTS:
Please leave a comment if you enjoy :)
Solution code: Row 8 from left to right
Comments
on 29. September 2025, 18:56 by BabyfacedBard
Complicated this for myself massively by thinking I had fo figure out if the diamond on each line is the end or beginning of an index line, only realizing halfway through it says it in the rules. Lovely sudoku anyway
on 26. April 2025, 08:57 by ninjamunk
I saw the four stars and thought it would be too hard. But it was quite approachable, and I rate the difficulty 3 stars.
As for the enjoyment, boy oh boy, Marty is in a category for himself.
Very Nice for most his puzzles are understatements.
This was no less.
on 14. April 2025, 06:00 by dpatti
This was such a satisfying solve. Something about this must have worked for my brain because the flow was almost magical. Thanks!
on 22. March 2025, 21:17 by PancakePie
Boy oh boy did I get sucked into PencilMarking! But I did love some of the foundational realizations the line limitations created! Very fun once I found a flow, though it took me a few long sits to crack some of the logic.
on 23. February 2025, 13:55 by cafce25
"lies at one end of its index line" convinced me I had to figure out which end (beginning or end) so much so that I overlooked the fact it's the start in the INDEXING section about a hundred times reading over it. After that bit of reading comprehension was out of the way the puzzle was a breeze. Really enjoyed it.
on 22. February 2025, 01:42 by Asparagus
A great mental workout!
I wasted time at the start by not reading all the rules. All the more enjoyable once I saw the one I'd missed!
I am continually impressed with the different twists in every puzzle - well done again!
on 18. February 2025, 20:33 by mscha
Oof, that was hard. I gave up many times, but I kept coming back and discovering a new consequence of the rules and getting a bit further.
Wonderful puzzle!
on 10. February 2025, 01:14 by Bionic Cheese
Fantastic puzzle , really enjoyed it
on 6. February 2025, 01:33 by softie
It took me a little while to grok the rules, but then once I did the solve path was so satisfying! Amazing how you set this up to keep providing resistance the whole way through.
on 5. February 2025, 14:27 by jakestilesowen
Truly amazing how few clues it takes.
on 5. February 2025, 04:58 by anormalperson
Great puzzle! Quite approachable once you understand the whole rulesets
on 3. February 2025, 22:15 by ElenaMonteille
That was fun, many thanks to both authors!
on 3. February 2025, 21:03 by OrestisLomis
One of those puzzle where through incredible setting the solver is left feeling special because they were able to solve a puzzle that seemed impossible from the starting constraints... well in my case I did feel quite stupid because for the longest time I didn't realise there could only be 1 diamond in each row and column as well. But once I realized this the puzzle solved very nicely!
on 3. February 2025, 01:08 by jwanders
Loved it! Wonder if there's an arrangement where all the line ends are also rcb?
on 2. February 2025, 17:46 by sanabas
Fun idea, great puzzle. Extremely approachable once you absorb a key point from the rules.
on 2. February 2025, 13:23 by Franjo
Fantastic idea, fantastic setting, fantastic puzzle! And approachable, so I gave 3 stars. Thank you very, very much for creating and sharing this beautiful gem.
on 2. February 2025, 08:02 by LehanLehan
Very nice puzzle,it has a feel of both authors. Thank you very much.
on 2. February 2025, 04:08 by vitaminz
Always lovely to collaborate with you. I think this one turned out even better!
