Colour Coordinated Differences
(Published on 22. October 2025, 13:27 by marty_sears)
- A pink arrow contains two consecutive digits.
- A green arrow contains two digits with a difference of at least 5.
- On a black arrow, one digit is double the other.
Rules:
Normal sudoku rules apply.
The two digits on an arrow give the coordinates of a particular target cell somewhere in the grid. The digit on the arrow's shaft indicates the target cell's row, and the digit on the arrowhead indicates the target cell's column. The difference between the two digits should be placed into the target cell. No two arrows target the same cell.
Also:
Solution code: Row 9 from left to right
Comments
on 3. February 2026, 21:42 by Jasperrr
Interestingly, I found this one harder than the "Colour Coordinated Sums" which is rated 3*. Ratings should be swapped imo.
Marty: I quite often disagree with the ratings, but the average opinion of lots of solvers is always gonna be the best measure of it, assuming everyone is rating honestly
Jasper: That's very much true. Some puzzles will just click better for some people than for others. Anyways, lovely puzzles, thank you!
on 23. January 2026, 13:37 by FifthWorld
Instead of solving the puzzle, I didn't fill in the last digit, thinking I had broken it. I checked Simon's solve and apparently he had the same digits I had, so I had another look and found the error was only in my head.
on 22. January 2026, 11:59 by Schwupel
"No two arrows target the same cell."
Is a very important sentence. Was stuck on the puzzle for way longer than I want to admit until I reread the rules.
Such a clever puzzle! Very fun to solve.
on 19. December 2025, 10:56 by Fredxl
Ugh, this is unbelievably good. It’s genuinely moving!
on 7. November 2025, 17:28 by ThymePass
Very clever and with an optimally positioned set of clues to keep the solve going smoothly. That was a lot of fun!
on 5. November 2025, 01:41 by zardoz37
Totally brilliant and original logic from Marty Sears.
on 4. November 2025, 09:38 by SirRanch
It's been a while since I felt compelled to praise a puzzle in the comments but this certainly deserves it. Such a fun solve path. Also, was the arrow easter egg intended Marty? That gave me a chuckle
Marty: haha thankyou, which easter egg do you mean?
If you color all the potential cells for the pink and black arrows (before narrowing it down) it kinda forms an arrow which I thought was neat
on 1. November 2025, 15:49 by Klausku
Brilliant puzzle. How do you come up with these ideas? I love the finish. Thanks again, Marty!
Marty: this particular one was inspired by a puzzle by Piatato called Coordinate Arrows - you should check it out, and Simon's solve of it on CtC which is one of my favourite videos on the channel
on 31. October 2025, 00:54 by Piatato
Very neat solvepath, thanks!
Marty: very happy you enjoyed it. I shouted you (and your original puzzle) out in my comment on this evening's feature on Youtube :)
on 30. October 2025, 23:21 by RoystonDA
Loved this! Creative way to incorporate indexing with some classic variant rules. The break in for it took me some time to understand but was a fun discovery.
My solve time was a little faster than I expected, so I've marked this as 2*. Keep up the fun work dude!
on 24. October 2025, 18:27 by razor2811
Absolutely Beautiful Puzzle, but that break-in is definitely 3 Stars of difficulty not 2.
on 24. October 2025, 14:46 by davidz32z
Wow this one was incredible! Some very new logic for me that I think is worth 3 stars, but what an incredible (new?) rule set!
on 23. October 2025, 17:44 by Olive
Great puzzle, thank you :)
on 23. October 2025, 12:50 by Franjo
Funny indexing ruleset! Love this. Thank you very much for creating and sharing another beautiful puzzle.
on 23. October 2025, 10:30 by ThatUnfunPerson
Like most marty_sears puzzles it seems impossible at first, but is surprisingly approachable. Especially when you realise the arrows are kropki dots and german whisper lines with some extra pizzazz.
Everything falls into place once you start thinking about the possible locations and values of target cells.
on 23. October 2025, 10:18 by mscha
Wonderful puzzle with a brand new ruleset. This is one of those puzzles that seem impossible, but once you figure out how to get started, all puzzle pieces fall in place nicely.
on 22. October 2025, 22:28 by bboom
Very cool puzzle. The color scheme works very intuitively, since the green and pink arrows are effectively just very short whisper and renban lines.
on 22. October 2025, 21:00 by elyas_targ
A very pleasing puzzle, I really enjoyed starting with the geometric coloring of possible target cells and working from there.
on 22. October 2025, 19:29 by psych
incredibly creative, simply brilliant!!
on 22. October 2025, 18:37 by CitrusGremlin
Do the targeted cells have to be on the line emanating from the arrow? Can targeted cells be on arrows themselves?
Marty: A target cell can be anywhere, including on the arrow that is targeting it :)
