RAT RUN 27: Productivity
(Published on 25. February 2026, 01:01 by marty_sears)
- Normal sudoku rules apply.
- AIM OF EXPERIMENT: Finkz and Phinx must both reach different cupcakes by finding a path through the maze. The paths must not visit any cell more than once, share cells, cross themselves or each other, or pass through any thick maze walls.
- As well as moving orthogonally, they may move diagonally if there's a 2x2 space in which to do so, but may never pass diagonally through a round wall-spot on the corner of a cell.
- GOLDENBERRIES: If two digits are joined by a goldenberry, they are NOT consecutive.
- TEST CONSTRAINT: In this experiment, both paths are divided into segments by 3x3 box borders. Along a path, the digits on each segment have the same product (the result of multiplying the digits on the segment together.) This product may be different for Finkz and Phinx. Note: if a segment contains only one cell, that digit is considered to be the product.
Solution code: Digits not visited by either rat in row 3, from left to right
Comments
on 24. March 2026, 22:29 by DaniK
Beautiful puzzle!
on 4. March 2026, 15:57 by docpayce
This was HARD for me to be perfectly honest. But I was really pleasently surprised how limiting the seemingly inconspicuous rules actually were. Never would have thought that those would be able to solve an empty (no numbers) puzzle.
on 1. March 2026, 05:36 by MikeMeech
Loved it as always!
on 1. March 2026, 02:11 by darkgently
As a maths lover, I didn't think this was harder than the usual Rat Run standard, but can see why others would. Poor Finkz getting trolled by the cupcake right next to her!
on 28. February 2026, 20:01 by Vionix
Very nice!
on 28. February 2026, 14:21 by nunc
I'm not sure who is the lab rat here... I guess it's us solvers. Thanks a lot for this one!
on 27. February 2026, 21:46 by Klausku
That was not easy, but not the hardest Rat Run puzzle so far. 2 hours of pure fun for me. Brilliantly constructed, again. Thanks Marty!
on 27. February 2026, 21:25 by DonQuichopp
Hard but for a 4* actually quite approachable for me. It was quite easy to break in and then i struggled for a long time, then it continued well and then struggled again. After having solved a few boxes, then it flowed really nicely.
Thanks for another wonderful rat run puzzle. I am already sad that it'll come to an end soon ;-(
on 27. February 2026, 18:03 by monsen
This was so fun. It was hard, but just as with the rest of the puzzles in this series, the difficulty is with the entire puzzle, not just some hard to find break-in, you never feel just stuck.
on 27. February 2026, 15:59 by KelleyCook
Very different and really hard. Many, many hours later, with numerous backtracks.
I don't think I've ever completed a puzzle this hard.
on 27. February 2026, 12:11 by Rab3aron
Amazing puzzle! 4* for me
on 27. February 2026, 05:05 by earthpuzzles
Never did learn my times tables, and likely never will, but fortunately algebra came to my rescue and this puzzle was an enjoyable solve!
Looking forward to the next one :)
on 26. February 2026, 22:37 by wuc
Home ground for math lovers. To me rather 3*. For once I tend to an easier vote than others. Another masterpiece anyway thx.
on 26. February 2026, 18:38 by Asparagus
This is an excellent puzzle, particularly the subtle way the two paths interacted. It was a joy to solve.
I am fairly certain that the goldenberry in Block 3 is not necessary, but am delighted that Finkz (or Phinx) is given an unexpected treat!
Marty: I'm fairly certain it is needed. The puzzle has 7 solutions without it. Glad you enjoyed :)
Thanks Marty! I've found the mistake I made.
on 26. February 2026, 03:15 by tallcat
This one foxed me more than the others - a nice start and then a brick wall to work through. But no less enjoyable for it.
on 25. February 2026, 23:59 by davidz32z
Definitely the hardest rat run yet! I find product puzzles a bit trying, but the charm of this one and the path finding really carried me through. Still so fun and I adore these rats <3
on 25. February 2026, 20:49 by crosslegged
Another awesome rat run. Took a while to get used to the product restraint, but after the first few steps, the logic started to flow
on 25. February 2026, 20:20 by blackjackfitz
Huzzah!
on 25. February 2026, 19:54 by Nairurian
Very fun, but considering I’m really bad at maths, it definitely wasn’t smooth for me (it took me over 2h).
on 25. February 2026, 19:32 by vitaminz
Surprised and delighted to get a puzzle like this from you. Like I imagine of the rats, I often felt trapped, finding no obvious way to make progress. But with some determination I was able to get to proverbial cupcake.
on 25. February 2026, 16:11 by GeorgeTheToad2
Not too hard for a mathematician but very enjoyable.
on 25. February 2026, 13:59 by Tortugo
I was feeling pretty smug having solved one path in about 15 minutes; not so smug almost an hour later having made almost no more progress.
Great puzzle as always.
on 25. February 2026, 13:53 by Franjo
Figuring out how the second path could work was quite challenging, but I enjoyed solving this puzzle so much! So, again thank you so much for creating and sharing another beautiful episode.
on 25. February 2026, 13:20 by mscha
Difficulty: 2 stars. For Phinx.
4 stars for Finkz.
Very nice, of course; that is a given for a Rat Run. :-)
on 25. February 2026, 11:26 by Christounet
My brain experienced a productivity failure while I was trying to process the factors options. Until I eventually recovered and asked the right questions. Enjoyed the workout! Thanks :)
on 25. February 2026, 05:53 by antiknight
Amazing and surprising deductions in this one! Great puzzle
on 25. February 2026, 04:25 by halfcentaur
Another outstanding addition to the greatest Sudoku series of all time! This was challenging, lots of math with the factors, but the logic flows beautifully.
on 25. February 2026, 03:53 by ArmagedDan
I usually struggle a bit with these ones, but I found the break-in pretty much straight away. Very nice puzzle, love the way the paths were pushed through the maze.
on 25. February 2026, 03:32 by chinesemaster
One tricky point mid-solve, the rest is smooth like butter! Thanks so much for yet another brilliancy!
on 25. February 2026, 02:45 by QuiltyAsCharged
This chapter is understated, with open spaces and much for the solver to discover. A good and robust challenge!
on 25. February 2026, 02:45 by Atticus837
Found this one harder than most, but it's a really interesting one. Lots of mental work on the factors to find the ways the lines can multiply out.
I'm earlier to this one than usual too it seems...
Great puzzle!
on 25. February 2026, 01:03 by sujoyku
I found this one very hard, but what a fantastic challenge it was. Thank you for this superb puzzle, Marty!
