"One Of The Best Killers I've Ever Solved"

[@mariushutu9131]

It is remarkable how you can spot the most complicated logic, but dont see the black 9 in the corner resolves the 39 pair in column 3 for like 10 minutes. Great solve, as always

[@KyleBaran90]

Or watching Simon solve it and spotting the coolest logic, or solving cryptic crossword puzzles, but then not realizing that the name is an obvious reference to high/low digits attracting each other (eg working out the cage differentials)

[@listey]

A lot of solvers struggle to see the black digits for some reason.

[@MrDaDisha]

it's not like he was staring, doing nothing and not seeing. he was doing the other part of puzzle writing numbers and making progress.

[@Piatato]

How amazing to be able to watch this one twice! 😲 Will watch right now 👀

[@CarlintVeld]

The first time you solved it yourself? Thanks for this great puzzle!

[@bobblebardsley]

I'd guess the title stems from the 'polar opposites' of sudoku digits being the digits 1 and 9 (or 'low' and 'high', more generally). The high-value killer cage 'attracts' r1c1 towards being a high digit, whereas the low-value cage 'attracts' it towards being a low digit. Finding the equilibrium between those attracting forces is the key to breaking into the solve.

[@Piatato]

Thanks for another great feature of this puzzle! I had a lot of fun watching both. I hope Mark won't get too annoyed by the fact that you were a bit faster - I think he was a bit distracted by wanting to trifurcate every cell in the grid. 😛 In the end you both found all the same logic, though! Just awesome! 🥳

[@philc2729]

But why polar attraction though, per his question?

[@OlafDoschke]

That's weird. I thought this was done before, but couldn't remember if it was here or elsewhere.

[@Paolo_De_Leva]

The hardest deduction was beautiful but extremely difficult to find. Simon, as usual, grasped it quickly and skillfully, at playback time 27:18. I admire Simon's genius but I also sympathize with Mark. I am glad this puzzle was solved by both Mark and Simon. It is a masterpiece, full of cool logic, and it fully deserved a double feature on CTC. 👏👏👏👏👏

[@Paolo_De_Leva]

By the way, there are other puzzles that would deserve a second feature on CTC...

[@pacman52280]

When/Where did Mark solve this?

[@AndersHaalandverby]

(edit: Click on My name to see my video on the alternative break-in! )My break-in to this puzzle was completely different! I used SET THEORY on column 3 and 4 and row 3 and 4, if you subtract the cages and the virtual 13/7 cages in the big cage, you are left with the intersection of the two columns/rows MUST add up to 20! and everthing else(not in any cages) in the rows MUST be MAXED OUT, and everything in the 2 columns that not cage must be MINIMIZED. If you make the 20 intesection 1 bigger or 1 smaller, nothing works!

[@Piatato]

Very nice, it actually seems to totally bypass the main breakthrough that Simon found, in a legitimately very beautiful manner. I didn't realize this earlier. Thanks for explaining!

[@AndersHaalandverby]

I've made a video as well with the explanation a little more obvious, just click my silly face on the left to get to it.

[@olegpovkh5581]

This is the hardest puzzle I have done, it took me 86 minutes, I'm so proud right now, thank you CtC, with out you I never would have even attempted it.

[@christophejefferies522]

Here's Mark's solve of the same puzzle: m.kzbin.info/www/bejne/q33JeJZvfbSUb5I

[@stevenape377]

So, he did beat Mark's time :)

[@Paolo_De_Leva]

Thanks. I thought that KZbin automatically rejected comments containing links (except for *Wikipedia* links). P.S. Now I realized you can post KZbin links only if your comment is not a reply. What a questionable and annoying policy.

[@RichSmith77]

​@@Paolo_De_LevaOh, I never knew that. I always wondered why some of my comments with links seemed to be deleted and others weren't. I agree, no rhyme nor reason for it.

[@Paolo_De_Leva]

@@RichSmith77 They don't even warn you. It's a very unpolite behaviour 😤

[@Kyufoxy]

@@Paolo_De_Leva (Spam) links in replies can be added to the most popular comment and noone can prevent them from being attached to it. They will always stay at the top of the page. In their own comment thread on the other hand they can simply be ignored/downvoted (if that even does anything anymore) until they end up at the bottom of the page. Makes perfect sense to me why only replies are blocked. The Wikipedia thing however, idk lol That being said, there's always the option for the channel owner to allow all comments via the channel settings.

[@stevieinselby]

Having large digits *on* means that when you corner-mark a digit into a clued cage cell, the corner mark and the cage clue overlap and it can be hard to read the cage clue - having large digits *off* means that the pencil and corner marks are slightly smaller and so stay clear of the cage clues.

[@jefffrank177]

And the thing is the digits aren't actually larger, they are just moved slightly more toward the center. This is a setting I think Sven should just remove and always have the corner marks more toward the center as in "large digits off" mode.

[@CrankyOtter]

I just want corner marks to be right justified. It incompatibility messes with my brain when corner marks are on the left, in addition to covering cage clues.

[@kevinthedood09]

I love your channel and your content Simon and Mark, thank you!!!

[@13vatra]

My guess is that it's called polar attraction because you're able to pencil mark and distinguish between opposing digits in row and column 2 because of how the cages interact.

[@jestfullgremblim8002]

Exactly!

[@six_5000]

✏ 15 minutes of intense goodliffing 😵‍💫 45 minutes of clueless staring 💡 revelation!! 🌨 15 minutes of digits blizzard

[@insttinct9083]

I have no idea how I found this channel but I'm glad I did, somehow every video is both relaxing and interesting. Great people, great videos, thank you :)

[@JohnRandomness105]

Once I saw the 24 and 16 cages where they were located, I remembered solving this puzzle. After getting stuck a couple times, maybe breaking the puzzle a couple times, I used a math theorem to fill out those cages. I didn't prove they absolutely had to be, but they fit everything else I'd penciled. The theorem: 1 + 3 + 5 + 7 = 4² = 16 and 3 + 5 + 7 + 9 = 5² - 1 = 24. So I placed the odd numbers 1357 in the 16 cage and 3579 in the 24 cage, and finally solved it. I discussed it with the setter in the comments of a Smart Hobbies puzzle. However, this has to be easier than the puzzle I watched yesterday, a killer Sudoku by Phillip Newman. On the other hand, I was up until 6AM trying this puzzle the first time.

[@CrankyOtter]

Thanks for this comment. I started playing with the numbers & there are lots of patterns in 4 consecutive odd numbers! where A+B+C+D are 4 consecutive odd numbers, find the square of the top placement (7=4th place) less the square of the missing placements (D+1)2 (A-1)/2 so A+B+C+D = [(D+1)2]^2 - [(A-1)/2]^2 & is also a multiple of 8 & = 4A +12

[@JohnRandomness105]

@@CrankyOtter Nice!

[@owenchrisfianwijaya4603]

Interesting. I feel like i got deja vu watching this video..... Edit: i just read the description, and it does confirm my deja vu. Great solve as always 😊

[@andrewnelson2525]

I thought I was going crazy. I was sure I'd solved it before! (I looked the old video up and I solved it 30% faster this time.)

[@inspiringsand123]

Rules: 02:47 Let's Get Cracking: 03:32 Simon's time: 36m34s Puzzle Solved: 40:06 What about this video's Top Tier Simarkisms?! Three In the Corner: 1x (35:40) Maverick: 1x (00:23) And how about this video's Simarkisms?! Ah: 12x (05:38, 14:02, 14:14, 18:13, 19:05, 21:33, 22:12, 22:31, 22:50, 27:17, 35:45, 36:42) Sorry: 9x (00:27, 09:16, 09:44, 10:25, 11:21, 15:19, 19:44, 23:37, 24:09) Hang On: 9x (07:20, 13:36, 13:42, 13:46, 13:49, 17:00, 19:35, 27:47, 30:36) By Sudoku: 6x (06:23, 15:58, 18:26, 18:32, 19:15, 34:24) Clever: 4x (22:53, 27:29, 27:34, 38:12) Brilliant: 4x (00:31, 00:34, 38:47, 38:51) Pencil Mark/mark: 3x (11:04, 23:06, 23:11) Symmetry: 3x (16:33, 19:58, 20:08) Naughty: 2x (39:56, 39:58) Lovely: 2x (00:45, 29:58) Beautiful: 2x (18:37, 34:10) Fascinating: 2x (21:40, 38:08) Nature: 2x (28:43, 28:54) What on Earth: 1x (24:13) Goodness: 1x (31:05) What a Puzzle: 1x (37:25) Naked Single: 1x (35:45) Nonsense: 1x (25:23) Magnificent: 1x (21:33) In Fact: 1x (33:39) Obviously: 1x (05:24) Full stop: 1x (37:41) Whoopsie: 1x (34:20) Phone is Buzzing: 1x (19:50) Fabulous: 1x (30:30) That is Sick: 1x (27:26) Most popular number(>9), digit and colour this video: Sixteen (7 mentions) One (75 mentions) Green, Orange (30 mentions) Antithesis Battles: High (18) - Low (18) Even (4) - Odd (1) Black (5) - White (0) Column (12) - Row (8) FAQ: Q1: You missed something! A1: That could very well be the case! Human speech can be hard to understand for computers like me! Point out the ones that I missed and maybe I'll learn! Q2: Can you do this for another channel? A2: I've been thinking about that and wrote some code to make that possible. Let me know which channel you think would be a good fit!

[@snouthlly1479]

“7 minutes ago” This guy: I can watch and analyse this hour long video in 7 minutes.

[@mickaelladouglas4373]

I love this bot lol 😂

[@SiderealDay2356]

Mark's solve kzbin.info/www/bejne/q33JeJZvfbSUb5I

[@snouthlly1479]

@@mickaelladouglas4373 thats a bot? If bots are gonna do this I don’t mind them existing.

[@williammorris7279]

I may be wrong, but I noticed there have been no birthdays recently, coinciding with a gokf tournament, which could mean this is pre-recorded, and that may be why we are seeing a duplicate puzzle. It seems to be a clue when he does not say the day of the week in his welcome. OK, maybe I am watching this channel too much! Golf, obviously, not gokf!

[@longwaytotipperary]

❤ the patchwork quilt and Simon’s reading the poem. Didn’t we get Simon reading/singing to us as part of the new puzzle book! Where are they in that?

[@Igshar]

A bit delayed on finding this, absolutely brilliant solve. I just wanted to point out an additional point of beauty in the final solution in that the entire puzzle is perfectly symmetrical, if you pair the opposite number pairs (1-9, 2-8, 3-7, 4-6, and 5 is symmetrical on its own) along the main negative diagonal from NW-SE. Coloring each pair the same color makes this become obvious once the solution is completed. Such a fun solve and such a great logic puzzle.

[@maxx-er3fj]

I have seen that at the end. Almost all sets where you change coordinates becomes 10-first number. So A(x,y) is 10 minus B(y,x)

[@psiphiorg]

My time today was 48:48, and I was solver 969. I used low/middly/high coloring, then using letters to distinguish them (ABC=low, DEF=med, GHI=high), instead of every digit getting its own color. Ran into a bit of a glitch due to mistakenly swapping one low and one middly digit (row 2, columns 5/7). Had to backtrack a bit to find my mistake then put them the right way around. Fun!

[@crystalgehrt8861]

This was such a pretty puzzle. Just a wonderful use of symmetry, balance, and logic! Take a bow and have a piece of cake @Piatato

[@awebmate]

I struggled a lot with this puzzle when Mark published it, and i haven't forgot it. But cool to see Simon's take on the same puzzle. Yesterdays 4 star puzzle is easier than this 3 star puzzle imo. With little information you know where to look, while with more information, it is harder to spot what is relevant.

[@andychou1069]

If I remembered, this puzzle is solved by Mark on the other day. But I still find it interesting watching Simon solving this.

[@alexstruijk8121]

Yes indeed, it was solved by Mark two months ago. Called "A Clear Ruleset and an Opaque Puzzle". But at least Simon did it a lot faster (about 15 minutes faster). Fun thing is, apparently there is only one way of solving it as they both did it the exact same way. Still loved watching it though. I always do, even though Simon often gets distracted and has to do the same logic over and over again and Mark somethings skips something and makes a mistake and 'wiggles' his way out of it. Never stop

[@pacman52280]

​@@alexstruijk8121, thanks for the info. I had wondered when/where Mark solved this because there was another comment on this video that mentioned it.

[@SiderealDay2356]

kzbin.info/www/bejne/q33JeJZvfbSUb5I

[@stevieinselby]

When Mark posted the puzzle, I tried it and got stuck and gave up. This time I solved it in 45 minutes - while I didn't specifically remember that I had seen *this* puzzle before, as I did it the _logic_ around pinching the digits into HML felt familiar.

[@titusadduxas]

1:41:56 - I’m so chuffed to have completed this one unaided. I loved the link up between the 13 & 7 cages but struggled a bit to narrow the options down after that. Mind you when I started on this channel a year ago I wouldn’t have had a clue what to do!

[@pg5200]

That was beautiful ! I had another different break-in : I saw that the addition of the two top right cages had to contain 1, 2 and 3, and that the addition of the two bottom left cages had to house 7, 8 and 9. Then I substracted respectively 6 and 24 to the totals and a bit of maths lead me to a difference of only 4 with one large digit on one side and one small digit on the other, therefore becoming forced 3 and 7. This one took me well over an hour to figure out ^^

[@dilbert719]

A wonderful solve in 49:58, that would have been much more efficient had I not spent what felt like hours, but must at least have been minutes, forgetting that once I knew the value of either C3R8-9, or R3C8-9, I could then remove basically every candidate from the other half of those boxes but the correct ones. (I felt like the sharpest bulb in the box when I realized there was only one suitable way to comprise those pairs of digits out of remaining candidates, let me say.)

[@srwapo]

63:36, terrible job. I was stuck working on the 16 and 24 cages, colored some cells in the corner as a "worksheet" to figure out that three of the cells in each cage had to be the same and the different cells had to be a 1 or 9. When I did the coloring, I picked a random color for the 456 cell and it led me down a horrible path for like 20 minutes before I realized the mistake. Seems like I wasn't able to solve in the last time this puzzle came up, so I guess I got better in the last two months!

[@walrusahoy5878]

I was thinking “polar subtraction” due to the 1-9 deduction after the 24, 16 cage subtraction - amazing puzzle

[@stevesebzda570]

There, Simon (@4:09 - you wondering if the "large corner marks" should be turned-off). Yes, turn the large digits "off." The smaller corner pencil-mark there will enable you to see the cage total. Being you were asking.

[@phuybrechts6875]

Hi , Simon .Nr 3 here , 5 in the corner needs NO song , thanks

[@dannstarrjp]

The logic in 29’ was absolutely brilliant, I didn’t spot it and it took me 1.5h to solve the puzzle through trial and error😢

[@Sam_weiqi]

37:04 for me. Fully agree with the title. What a brilliant break in.

[@happydommo]

I knew I would love this puzzle just from the title of the video and it kept me occupied on a rainy camping trip. Looking forward to watching (both) the solve now....

[@bait6652]

The fun part is to see how much u can solve w/o the given 6&9...once u work out theres common H/L, u can work most of the colormapping aside from 46 using the 2 adj dominos...very nice layout...discovering the common mid in the squares was nuts, only saw it on the second solve ...how he sees it without pen is crazy. Solving w/o 6 and 9 creates 2 systems of digits that cant be resolved without the 2 givens...nicely done Especially like the 2 squares could be 4 dominos 3 distinct pairs for 12 and 8 sums

[@mrsawiggins]

Boxes 3 & 7 are polar opposite, and they both attract to box 1. :-) I definitely loved this one.

[@fulltimeslackerii8229]

that trick you did with the red being 9 can also be used with the 13 and 7 cage to get 2 and 8.

[@crystalgehrt8861]

Sometimes you wish you could give a puzzle two likes!

[@watcher314159]

I predicted the difference of 8 would disambiguate everything immediately upon starting the puzzle. Simon has done enough puzzles that resolve that way that it seemed pretty obvious. Actually proving it on the other hand...

[@dragonflyer10000]

also something you didnt notice is that the two cages without numbers in the left corner every number added to 10 when paired with each other in the opposite side. so the bottom left and top right is a 4 6 pair adding to 10 overall.

[@davidtieman4102]

Wonderful Puzzle. There is symmetry around the diagonal with almost all opposite cells adding to 10. I colored the diagonal green, lower digits blue, higher digits red, the same digits purple, and the cells that are different yellow. Not sure if that was the reason for the name, or if the pattern was on purpose, but wonderful puzzle.

[@michaelhoffman2011]

Finished it but I have a very strong sense of deja vu. I feel like this puzzle has been on the channel before. Not complaining cause it is a very fun puzzle to figure out

[@Raven-Creations]

That was sublime setting. I had essentially the same approach. I had expected the 8 cage in C9 to be crucial in the disambiguation, because it had to contain a 123, but that meant it contained either 56 or 7. I was expecting it to need a high digit. As it happened, it was the 16 and 24 that did all of the magic. A good solve from you today. I don't think I shouted once, although I couldn't understand why you resisted filling in the 6s in green for so long. I'm not sure if the 8 cage was required, or whether it was put there as a red herring. I do wish you'd stop using blue and purple, which are identical for colour-blind viewers, to "distinguish" two of the same class of digit. A blue 123 and a purple 456 would have been fine, but a blue 123 and a purple 123 just looks like two identical blue 123s. I really don't know how many times we have to ask you not to use blue and purple before the message gets through. It's not that they are difficult to tell apart, they appear identical. There must have been hundreds, if not thousands of comments requesting you not to do this, starting from when Sven first added colour to the app.

[@Sam_weiqi]

I assumed polar attraction was something to do with the 9's and 1's having to be as far apart as possible.

[@longwaytotipperary]

6 out of 9 times the 9 and 1 are next to each other, either horizontally or vertically. So maybe it’s opposite.

[@piarittersporn]

This is a very clever and adventurous puzzle and a good exercise for logical thinking. It took me a while to figure out the meaning of r1c1, r1c3 and r3c1 with the overlapping or common sums, but after that I was pretty quick on the way to the solution.

[@Jesthers]

Had to watch to 28:16 to solve. I think this one was a little out of my skill level, but that's alright! Was still a wonderful puzzle to solve :D I had colored way more than Simon did, so maybe I need to get better at identifying what needs coloring vs what doesn't, but that's more an issue of me not knowing where to look in general. I don't think I'd have figured out that the 24-cage and the 16-cage share three digits and I even had those three digits colored already. Honestly just my bad for not really looking at that while trying to figure out placements of other colors.

[@RichSmith77]

I managed to solve it 30 minutes faster than the previous time. This either means (a) I've improved more than I realised in just two months, (b) I attempted to solve it as I was falling asleep last time, or (c) my memory is a lot better than I thought.

[@stevesebzda570]

Lol. "You're memory is better than you thought." Funny. Do you know, I can remember seeing the Queen on television when I was 10, 11, or 12 ? And where I was standing (and all of my surroundings in that room). I remember the most unusual stuff lol (That's where I realized recently that the Queen made that "Maths" joke by the tutor) I remember the dumbest shyt, don't I.?! Lol 😮😂

[@TheGamma009]

This puzzle took me about 73 minutes, but I loved every second of it. I broke in using set theory on rows 2 and 3 vs columns 2 and 3, combined with the orange/green logic you did in the video and some cage math, and that allowed me to pencil mark a bunch of 123's and 789's all over the place. Then it just turned into a lovely coloring puzzle.

[@ElysaraCh]

at 34:20 that's actually a good point, the given 9 in the corner wasn't necessary for that step since 17 and 39 were removed from the cages by the row/column logic anyway. time to see if the 9 fixing the 39 pair in box 7 matters or not.

[@jonbrowne]

Absolutely stunning puzzle and a fabulous solve! Brilliant entertainment! Only CtC can do this!

[@Poet13xRatedRKO]

31:20 for me. I needed about 25 minutes to get the first digits and suddenly everything else was done in just a few moments. I think I didn't have anything like this before.

[@mrrobotman5299]

When I see videos that are under an hour I typically try to do the puzzle. I don't read the description or watch anything until I'm done and did that again here. The entire time I was saying to myself "this feels really familiar." Upon finishing I read the video description and now know why it felt that way.

[@KalikiDoom]

The poem was marvellous at the end of it!

[@Handel9000]

I love Simon's eureka moments! 💡

[@Gonzalo_Garcia_]

Well, I've obviously solved this one before. At least we get to see Simon and Mark solving the same puzzle!

[@Orenotter]

Forgive me if I should lack tact But I must point out this one fact. Two sides the grid shows. One has highs, one has lows. And you saw how those cages attract. I do believe that is the origin of the title.

[@jimwittes9275]

Broke it by doing some 90 math. R3C2:4+R3C7+R4C3:4 had to equal to 37. Only way that would work is to place two 6s in C3 and C4. Then there are 3 remaining boxes in C3+C4 that had to equal 10 and 4,2,4 was the only possible combination.

[@Arcessitor]

That deduction at 29:00 is possibly my favorite in any puzzle ever.

[@antibond]

Such a great puzzle! But if the right corner is a given 1 instead of 9, the puzzle solution is more symmetrical with each number’s counterparts (1/9, 2/8, 3/7, 4/6)!

[@martinyyt]

This was a nice puzzle. I managed to get half way through before getting "stuck". Luckily (?) this puzzle is made for bifurcation. Which square in the 24 box was a 7 and which was an 8? I tried one and it worked. Total time was ~100 mins or a bit more (for figuring out how to get started). I'll have to watch the video(s) to see how to break the 78 logjam logically!

[@juli29_pp]

The title might be related with the great majority of the numbers at each side of the NW-SE diagonal being the 'oposites' (1-9, 2-8, 3-7, 4-6, 5-5)

[@damarisparker7348]

I think it's "polar opposites" because the two large cages are mirror number match images, if you know what I mean. Row 1 column 7 and Column 1 Row 7 are a 9/1 pair. Row 2, column 8 ad Coulumn 2 row 8 are a 6/4 pair. etc etc

[@Drakemier]

I think it was called polar attraction because of the 2 unnumbered cages on "polar opposites" of the puzzle giving you all of that information in box 1. (Almost as if it was attracted to box 1?) Random guess, not sure.

[@ewenfraser883]

Consider the sum of columns c8 and c9 and the sum of cages 7,16,8 and the given 9 the remainder is 50 and so the 3 remaining digits in c9 sum to 5 more than the sum of the 3 digits in cages 7 and 16 in c8. Also the 3 digits in c9 of cages 7 and 16 must sum to 5 less than the c8 sum of the same cages. Sum r1c9 + r5c9 + r8c9 is 5 more than and sum r2c9 + r3c9 + r4c9 is 5 less than the sum of r2c8 + r3c8 + r4c8 Did anyone proceed on that basis?

[@Urutsini]

I'd say "Polar Attraction" refers to one direction involving the high numbers and the other direction involves the low numbers.

[@songstressx871]

Him: I’m sorry about that. I think many of you will have gotten there miles before I did. Me, who was lost twelve seconds in and can’t even find what digits add up to 12: oh yeah for sure

[@ВероникаГулыманова]

Extended color panel is very useful. 3 shades of green, blue and red can mark both low-mid-high sets and digits 1 to 9.

[@MultiHaxzors]

My guess for why it’s called Polar attraction is that the 3 and 7 boxes are on polar opposite sides of the puzzle and their logic converges on the box they both influence, IE box 1, so their two logics in a way are attracted to box 1 creating said attraction from the two polar opposite corners!

[@Coyotek4]

50:57 ... I forget how long it took me the first time, but I sure didn't remember much considering how long it took me this time. Nice puzzle!

[@DarrenNakamura]

Took me just over 100 minutes to solve. I got very stuck in the middle but powered through it and found the interesting logic.

[@solarsystemwulf96]

"I'm sure some of you got there miles ahead I'm sorry" *me mindlessly following along because I like hearing you talk out loud and don't understand in low brain bliss*

[@mudscuffer]

Got some early progress coloring the puzzle... and then got stuck for quite a while. 54:50 solve time in the end

[@Deditzy.]

Well at least I could tell where the 9 in box 7 went before Simon questioned the use of the 9 in box 9! 😂😂😂😂

[@bait6652]

This design layout and its kins makes u wish someone will come up w progressive variant similar to fog but instead giving hints in the form of given digits. See how far the authors can go before asking for digit(within an aloted time target)

[@oddbarnett]

Always disappointing when too many colors are being used, and I have to stop watching the video.

[@Laezar1]

wasn't this one already posted? I remember playing one with very similar logic

[@ayannababii]

I got stuck after coloring in 2/3 of the puzzle. I did not think to look at the 16 and 24 cages.

[@wanderlustwarrior]

47:23 for me. I made an error I was able to spot. I remembered we've done a puzzle with this exact geometry before.

[@Wallopy_Joe]

Simon - "This 9 does nothing!" 3/9 pair on the left - "am I a joke to you?"

[@debrawilden1971]

(For me, there is no need to color all the digits. I'm with Mark in this that he gets rid of all the colors when they are no longer needed, cleans up the grid.)

[@alyssaharger6992]

Every time he said “oh I got it” I was like “he finally saw the 9”… that was never what he was taking about

[@romasteve7292]

would not have spotted 'the thing' but when you highlighted where it was I got there on my own, so kind of proud :)

[@cjslayer5128]

did anyone else notice the if you folded the sudoku across the top left and bottom right diagonal all the numbers the layer on top of each other equaled ten

[@spenserthomas5450]

6 & 9 are flipped opposites, and also, 69… nice. Hence, Polar Attraction

[@magicalawnmower4764]

i think the polar thing are the starting digits being upside down versions of the other, thus being in different “poles”

[@hayleymiddleton474]

Yep, send some of them on a special vacation. You could then put up a statue for the rest to remember their sacrifice!!

[@alanclarke4646]

I went totally wrong and gave up. Edit: went back later and managed to solve it.

[@PineappleDealer37]

I think its called polar attraction, because it's symetrical on a diafonal line

[@marcosdiez7263]

I'm pretty sure Mark has solved this several months (perhaps more than a year) ago.

[@raysouth1952]

Lovely puzzle. Beautifully put together.

[@AlexanderScholten]

Fantastic, the 13 box green and orange was available for ages ;-)

[@dannstarrjp]

Solved it but in double the time of Simon. Really struggled with this one 😢

[@arifleischer8285]

I love someone asking what is the 9 in the corner when there was a 39 pair it solved that had been there for sometime

[@shteevuk]

I could have *sworn* I've seen Mark solving this one..

[@tehbertl7926]

Really interesting puzzle. After doing the first three rows/columns the same way Simon did it (i.e. shading and getting pairs), I worked out some digits by doing some arithmatic and determining the orange digit in r1c1. (SPOILERS BELOW) If the orange digit were 6, then you would get 1-6 / 6-7 pairs for the 7 / 13 cages. However, this would create a 2-3 pair in the 16 cage (1 in grey knocks it out of the cage altogether), and make the high digit in that cage an 8 or 9 (there is one high digit in this cage, and it is yellow, not the "green" 7), meaning the last digit in this cage would also have to be a 2 or 3 which is not allowed by the rules. Similar logic works if the orange digit would be 4: 3-4 / 4-9 pairs in the 7 / 13 cages --> 7-8 pair + 1 or 2 in the 24 cage = another 7 or 8 needed to get to 24. As such, the orange digit has to be 5, paired with 2 and 8. There is then similar pleasing logic to work out which digits need to join the low digits in the 16 cage and high digits in the 24 cages, but I'll leave that as an exercise for the reader. :)

[@RoderickEtheria]

6:24, how does Simon rule out r5c2 for the location of r3c1 in b4? The reason it must be the case is if he looked at where r789c1 would have to go in b4, but he didn't ponder this before making his claim.

[@jaeusa160]

He doesn't need to rule out r5c2 because r6c2 is the set point he's starting from. You're basically asking "How does he rule out r5c2 from being r6c2?" and that would be because both are in box 4... If you were starting at r3c1 trying to narrow it down, I can see the issue, but the logic is starting from r6c2. The logic he expressed was r6c2 must go in r8c3 or r9c3, so it goes in r123c1 somewhere. And 2 of those are green, and blue =/= green by b4 logic, so it's r3c1.

[@stevenape377]

The logic is the other way around. The blue colour is defined as the contents of r6c2, whatever it is. Simon then argues that that digit has to go in the 2x2 cage at the bottom of c3 (because it can't repeat in the cage nor in c2), and only then can the location of blue in box 1 be deduced.

[@simonmoore8776]

Simon proved that r6c2 must be in the 24 cage in box 7, therefore it could only be in r3c1 because it couldn't be green.

[@jessetingle9055]

110:42. I'm glad I stuck with it.

[@sebijacobs4071]

Simon doesnt know that he has 27 colours to choose from 😅

[@Kirbyfan87827]

Finished in 15:59 by following along with the video.

[@markmcb42]

I am a bit confused about how Simon deduced that the blue 123 in box 4 R6C2 must match the 123 in box 1 R3C1. It seems possible that the blue digit in box 1 could be placed in box 4 R4C3, which would then allow that same digit to be placed in box 7 in R7C2.

[@khoozu7802]

U think the wrong way, u should colour R6C2=blue, then look for blue cell in box 7, u can place it in R8C3 or R9C3 only, then by sudoku, the blue cell in box is located at R3C1 only

[@tomkinsg]

Loved it Simon and Mr piatato