"If You Can't Spot The Trick, You'll Be Stuck Forever!"

** TODAY'S PUZZLE **
The wonderful James Sinclair returns tonight with his latest puzzle, Quadrilateral. Unsurprisingly it's a magnificent sudoku and serendipitously seems to result in Eva Green making an appearance during the solve!
Play the puzzle at the link below:
sudokupad.app/james-sinclair/...
Rules:
Normal sudoku rules apply. Digits along a thermometer must increase from the bulb end. Purple “renban” lines contain a non-repeating set of consecutive digits in any order. Gold “nabner” lines contain a non-repeating set of digits, and no two digits on the same line can be consecutive (regardless of their position on the line). Along orange “entropic” lines, every set of three adjacent cells must contain one low digit (1-3), one middle digit (4-6), and one high digit (7-9). Digits in cells separated by an X sum to 10. Digits in cells with a shaded square must be even.
Jane Street's Bug Bytes puzzle is available here:
www.janestreet.com/bug-byte/
(Simon's solve of this puzzle is on Patreon.)
Maria's riddle: if someone asks me either of the questions "how old are you?" or "which year are you born?" I can answer with the same number. (Assuming you remove "nineteen hundered" from the birth year.)
** NEW SUDOKU HUNT ON PATREON **
We're delighted to share with you a brand new sudoku hunt themed around snake egg puzzles by Glum Hippo. If you've never tried snake egg logic puzzles before, prepare for serious fun - these sudokus are outstanding! Finish by May 20 to enter the competition!
Other treats on Patreon include:
- the Sumgeons & Diagrams sudoku by sunnyjum;
- Simon's latest forays into the world of Islands Of Insight;
- Mark's video looking at the new OneUp puzzle from Rodolfo Kurchan;
- his solve of Region Geometry by Emre Kolotoğlu (3hr 36min long...!);
- and Mark's latest solve of The Times Club Monthly cryptic crossword
/ crackingthecryptic
** GET OUR FOG KICKSTARTER DELUXE & OUR BOOKS **
Check out this link for the kickstarter books and Fog Novella we've created over the years:
coffeebean.games/product-cate...
▶ SUDOKU PAD - Use Our Software For Your Puzzles ◀
You can input classic sudoku puzzles into our software and help support Sven, the programmer responsible for the wonderful user interface we all use to play these puzzles everyday. The app also comes with 12 handmade puzzles from us:
iOS:
apps.apple.com/us/app/svens-s...
Steam: store.steampowered.com/app/17...
Android:
play.google.com/store/apps/de...
ALSO on Amazon: Search for “SudokuPad”
▶ Contents Of This Video ◀
0:00 Theme music & puzzle intro
1:34 Bernard Hill RIP
2:45 Simon vs Bug Byte - a new Jane Street puzzle
3:55 Happy Birthdays
8:46 Rules
12:15 Start of Solve: Let's Get Cracking
▶ Contact Us ◀
Twitter: @Cracking The Cryptic
email: [e-mail]
Our PO Box address:
Simon Anthony & Mark Goodliffe
Box 102
56 Gloucester Road
London
SW7 4UB
(Please note to use our real names rather than 'Cracking The Cryptic'.)
**************************************************************
▶ CTC FAN DISCORD SERVER◀
/ discord
▶ OUR BACK CATALOGUE - ALL CATEGORISED WITH LINKS!◀
tinyurl.com/CTCCatalogue
▶ NEW CRACKING THE CRYPTIC MERCHANDISE◀
teespring.com/en-GB/stores/cr...
▶SEND US PUZZLES TO SOLVE/CONTACT US◀
[e-mail]
▶FOLLOW US◀
Twitter: @crypticcracking
Instagram (for how to solve daily clues from The Times): crackingthe...
We also post the Wordle In A Minute videos on TikTok.

[@James_Sinclair]

Thanks so much, very excited to see this one on the channel! This may be a relatively recent puzzle, but the idea for it goes way back to zetamath's first nabner puzzle-while solving it I noticed a property of four-cell nabner lines (that I won't spoil here, but I suspect it comes up in the video), and this is what came out of my attempt to build a puzzle around that property. Definitely one of my tougher puzzles, so I'm glad it's been well-received. Thanks to everyone who recommended it! I should also mention that I publish five new puzzles every week at Artisanal Sudoku (can't post a link here, but it's not hard to find), all of which are a good deal more approachable than this one 😁

[@samueldeandrade8535]

The lines forming squares is one or THE best aesthetic choice I ever saw in Sudoku Variation puzzles. Congrats for using it.

[@samueldeandrade8535]

Oooh, Nabner lines have something to do with entropy! Edit: I meant 4-cell Nabner lines

[@jackk5024]

I took a look at the puzzle, got some of the immediate ideas of it, then couldn't crack it. Decided to take a look at the video and as Simon said "I notice something" I immediately noticed the property of the corners which cracks open the whole puzzle! Very cool, great solve path and very fun.

[@Paolo_De_Leva]

Thank you for this sublime present 🎁 you designed for us. As I wrote below in a separate comment, _"magnificent puzzle"_ (in video description) is an understatement‼ This is the most complex and at the same time elegant and brilliant set of interactions between clues that I can remember. Each of them (renbans, nabners, thermos, entropic lines and squares) contributes with some minor restriction. Only when considered together these *weak restrictions* create the *powerful magic* needed to "un-stick" yourself and break-in. _"World class puzzle"_ would be an understatement as well‼ In short, this is definitely a sublime *Cosmic* class artwork. 👏👏👏👏👏👏👏👏👏👏👏👏👏👏👏

[@Paolo_De_Leva]

By the way, I see Simon used *Phistomefel's theorem.* I did not. I guess you used it to construct the puzzle. Was that required to speed up the solve as well? 🤔 The *renbans* in boxes *6* and *8* are restricted by the entropic line, and I focused on their combined intractions with thermo and nabner in *box 9.* This magic then progressively ignited the other renbans, thermos, and nabners, and when its fire reached *box 1* in the blink of an eye the puzzle solved itself. 😍🪄

[@BijickY]

Fellow fans and viewers of Simon and Mark solving sudoku: please be kind in your comments. ❤I don’t want Simon to change anything just because he doesn’t want to upset us. In my humble opinion, the videos as well as the solving are wonderful.

[@richarddavy-smith6626]

Well put.

[@denizkaragullu6239]

What is the reason for this comment? Did I miss something in the video

[@aguy3896]

?

[@samueldeandrade8535]

​@@denizkaragullu6239 it became a little tradition to repeat a mantra like that. Some people here enjoy the idea that Simon is kinda sensitive to bad comments and want to protect him from time to time. It seems the origin of this phenomenon is the same as the one that motivated Simon's ending phrase, "... I enjoy the comments, especially when they are kind".

[@rmjarvis]

Probably precipitated by Simon's explanation of the entropic line. Usually he gives away a trivial consequence of the basic rule. Apparently some people have objected to that in the past.

[@blobz-1]

Guitar Intro! Yay!!

[@MaryVidal-pt8bx]

Come for the Sudoku. Stay for the guitar.

[@JOHNWYATT42]

At 46:24 why does the second 8 & 2 have to be on a renban line (apose to R1C9 and R9C1)?

[@Samhain_III]

I too am unable to follow this step.

[@CrackingTheCryptic]

I hadn’t seen that possibility but the same effect happens a different way pretty quickly. Once there are 5s in boxes 8 and 6 (which there are at this point due to all the even digits!), the renbans in those boxes must either be 234 or 678.

[@nekizalb]

@@CrackingTheCryptic Thanks for addressing this. I was also confused by the omission, but the 5 and 1/9 restrictions seals it!

[@ejvalpey]

Simon got lucky here. Glad it didn’t wreck his solve.

[@kevinharris9054]

The logic is to note that you can't have 3 2s or 3 8s in the nabners as you then have 3s (or 7s) in a row and a column which forces the nabner to break (by having 2+3 or 7+8)

[@davidrattner9]

Bernard Hill...great actor. Brilliant he was as Theoden!! Was also Captain Edward J Smith in Titanic. Great into music Simon!!

[@erenscott]

I also really appreciated the guitar homage to Bernard Hill. RIP

[@Wakaflockabach]

Only actor to appear in 2 movies with 11+ Oscar's each.

[@johnm2012]

I remember him as Yosser in _Boys from the Black Stuff_ but I am very old.

[@arcticcat74]

Very nice to play the theme for Rohan in tribute to Bernard Hill. Great way to intro. I watched all the great scenes from Return of the King last night when I saw the news.

[@rankinepiper]

'My body is broken. I go to my fathers. And even in their mighty company I shall not now be ashamed.

[@iuriikononenko9238]

One of the things making Simon my favorite solver for the puzzles, are the true emotions he expresses when finds really Interesting things, which can be suitable for a great party!

[@iwersonsch5131]

That break-in of counting the ones and nines in the Phistomefel ring was absolutely marvellous!

[@debrabowen4276]

I love watching Simon’s thinking process. He carefully assimilates the rules of each puzzle’s world, and I love watching that!

[@LeeNotSa]

I can absolutely understand getting distracted by the thought of Eva Green!

[@myrtinyrtti]

I WHOLEHEARTEDLY LOVE THIS CHANNEL

[@Millenassang]

Oh yes this guitar intro! I recognised it right away! Way to go Simon that you very much for that! RIP to one of the protagonists of one of the great film series!

[@user-ox9oo6wp6d]

Never thought my comment could ever be one of the title of CTC video! It makes my day! And awesome guitar intro!

[@Paolo_De_Leva]

It was a nice comment. It deserved to be used.

[@TracyCarolan]

What was the trick that you used? I can spot several time-savers but not any that would enable me to complete this in 17 minutes!

[@user-ox9oo6wp6d]

@@TracyCarolan I solved it exactly the way Simon does in the video. But I fortunately spot the trick so quickly, so yeah, 17 mins for me.

[@jdyerjdyer]

You must be a genius at 17 minutes, lol. Spoiler warning: I spotted the geometry, and half of the 19 renban trick immediately and it still took me several hours as I kept getting stuck on where to proceed after I had filled in the orange line, box 8, then 6, and then 9 with a lot of deductions and a handful of digits. Maybe I was just tired, though. I didn't spot the 456 triple in column 6 for so long that was just staring me in the face, and I missed a 123 triple for a good ten minutes later on. The killer for me, though, was not having the forced 1 and 9 on the renbans in row and column 1. It required a bit more work to resolve that without that half of the trick. I definitely think my time would have been barely over an hour otherwise, which is more on par for my time compared to CtC's. Thanks for the warning, but too bad I didn't listen. lol, still I'm a little glad I did try it anyway as this puzzle was very beautiful.

[@jdyerjdyer]

Btw, the way I did end up resolving it was looking at column 1 and the interaction on box 7. My experience with nabner lines was non-existent, so that also didn't help. Thank goodness the geometry just screams at you and with a little logic you can see which boxes (2 possibilities for each rotated clockwise or counter-clockwise) each of the 16 outer ring digits go, even if you can't place them on the golden lines immediately. Btw--don't try and label the possibilities as they are a fuzzy set (2 from each grouping of four digits end up somewhere on specific golden rings forcing the other 2 onto another, but where they lie exactly...lol, I mean, you know that each renban contributes two digits to one golden line and the middling digit from that renban with the corresponding corner contributes two digits to another golden line. Not useful in the beginning, but can be used later if you aren't a numbers, let alone nabner lines, genius...

[@jdyerjdyer]

Wonderful puzzle, and absolutely right on taking a long time. I won't say my embarrassingly long time, but I will say that I did see the geometry and the added importance of the entropy line immediately. However, even though I quickly ruled out the 1 and 9 from the column and row 9 renbans, as well as the 5 which with the other clues gave me quite a few digits and some reductions in possibilities, I did not appreciate their requirement on the other two lines for quite some time, I did note that you had to "wrap" the 16 digits either clockwise or counter-clockwise into the golden lines, with two coming from the sets made up of the opposite corners and the "touching" renbans. In other words, say the golden line in box 1 was what you were looking at, it would require two digits from the set of column 1 renban and R9C1, and two digits from the set of row 1 renban and R1C9. This goes for each golden line, which is why I said the order is rotated one way or the other. While the digits can (and some must) be the same, you at least know where they have to come from. From here I focused on the box 8 clues and the box 6 clues to further deduce and eventually break the puzzle. The trick about the 1 and 9 for the other two renbans would have drastically reduced my solve time. Thanks for an enjoyable puzzle, @James_Sinclair and teaching me some more logic, Simon! Even though I took a longer trip with this one, it was enjoyable!

[@Gonzalo_Garcia_]

15:39 for me. Great puzzle! Love that almost every single clue is somehow important for the break-in.

[@guidosautter8329]

Great puzzle, great solve! Love the straight deduction logic without any constraint corollaries being dubbed "secrets"!

[@user-zu8vc5ef6w]

Wow, Simon really changed his appearance recently judging by thumbnail!

[@Ratzfaz]

for the easy proof, u can use row 1,9 and box 4,6 and for the other set column 2,3,7,8.

[@feldered]

Why other 2s and 8s could not be in the corners instead of renban lines?

[@hotwheelsnholdem4873]

yes that was what I was trying to figure out as well.

[@zhoppa]

pencil marks says that there could've been 2 and 8 in the corners at the moment of going ahead with 234 and 678 renbans. looks like a missing logical step

[@onurarabac7111]

you can not write 5s on renbans because of green 5s

[@RomanIgla]

You could fix this logic by thinking about 5s. There are already 2 fives in the outer ring, and you cannot have more than 2 fives in the squares. This will require to have 2 and 8 in renban lines.

[@SeanTBarrett]

@@onurarabac7111 he hadn't put in the green 5s when he first made the claim at 46:24, pretty sure he just forgot the corners applied to the set. he didn't make use of that until after he put in the 5s though, and it is a valid deduction after that.

[@TurquoizeGoldscraper]

46:59 for me - I've been having a bad day, solving a tricky Sudoku has boosted my spirits.

[@johnpauladamovsky86]

Simon is living through a surreal fantasy, where every single day, he gets to solve one-of-a-kind logic-puzzles, each of which is a sublime artwork-quality masterpiece. And in so doing, he has grown an audience with many thousands of puzzle enthusiasts who enjoy the puzzles even more than he does. There's something magical happening on the internet with these great puzzles. What an amazing way to ease into your 40's and 50's. Old men and internet-fame go together great, just like boats, and hoes...! Long live Cracking The Cryptic...!

[@fuxiascholz]

You had already a second 2 and 8 in the even pink corners, so the remaining sequences are not forced. Luckily it worked out for you, but I'd rather see a logical path. The puzzle is very clever, I enjoyed it a lot.

[@samc9516]

Such a nice tribute to have the Rohan theme for the intro to this video

[@bellamartinez2788]

That song is so beautiful! Very nicely played!

[@highpath4776]

1) Simon might like to pencil mark the even digits and 2) Simon is welcome at my parties

[@Vic-hy2ml]

I started solving the puzzles by myself and going to your videos when I am stuck, I really needed your help for the beginning but I managed to do the end by myself! quite proud ;) thanks simon! I'm starting to see geometry in sudoku more easily, that's really cool

[@guidosautter8329]

Regarding the extended Phistomephel ring, a proof without doble-selecting the corners works similar to the proof for the basic ring (the one that starts with selecting rows 3 and 7 and boxes 4 and 6, and then offsets that against columns 1, 2, 8, and 9): Simply start with rows 1 and 9 on top of boxes 4 and 6 instead, and offset against columns 2, 3, 7, and 8. Likewise, the second incarnation of the extended ring works with rows 2 and 8 on top of boxes 4 and 6, and offsets that against columns 1, 3, 7, and 9. And of course, you can swap rows for columns and vice versa, and use boxes 2 and 8 instead of 4 and 6, e.g. if the grid population makes one easier to follow than the other.

[@77kaczka77]

👍👍👍

[@angec9908]

“Even Green” love a good dad joke

[@RyanAtOptimism]

I don't get it?

[@gredangeo]

@@RyanAtOptimism It's a play on words of her name, Eva Green.

[@Paolo_De_Leva]

It was fun 🤣 @22:55

[@chipsounder4633]

Just loaded the video and i see SET instantly

[@Batmans_Pet_Goldfish]

I never did figure this one out. Time to take a look at what the trick is.

[@ericpraline1302]

This is a beautiful puzzle, full of elegant deductions. I had one particular sequence involving the entropic line and x which was sublime - Simon circumvented this. How somene could solve it in 17 minutes is beyond me. I prefer to savour the experience.

[@S00thsayer4]

Westu hál. Ferðu, Théoden, Ferðu. Great homage there, Simon. Thank you.

[@nonyobisniss7928]

I don't always listen to you telling us the rules first, so I'd rarely been spoiled, but this time I did and you just saying that you could say something but not saying it was itself a spoiler! Serves me right for rewinding to see what you'd said though, as I hadn't been paying attention until that comment about spoilers.

[@nonyobisniss7928]

Also, loved the guitar intro! What a brilliant film trilogy. The puzzle wasn't bad either, 55 minutes.

[@MattYDdraig]

12:51 Wow. That opening is incredibly intricate (and thankfully well sign-posted) but absolutely beautifully in the sequence of details needed to bring it all together. Bravo.

[@LiquorStoreJon]

If it's from James, this should be a great solve. And if you haven't subscribed to James' weekly email sudoku newsletter, you owe it to yourself to do so!

[@piarittersporn]

Brilliant puzzle.

[@AnnaChiaraBellini]

Ah, loved this! I still have to watch the video, see if I missed anything. A bit annoyed with myself that I had misread the rules and I was using modulo lines instead of entropic lines, which honestly made the puzzle impossible to untangle! But I learned that, if I can't figure something out, it's either set, or I got the rules wrong. I couldn't figure out any more set than I already had, so.... I'm glad I persevered, it was a fantastic puzzle to solve

[@mstmar]

great solve as always. my solve went almost exactly the same. i.e. fumbling tor 30 mins then spotting the trick i did spot a small mistake at 46:20, where simon said that the 8 has to be on the renban, but at the time it could still be in the corners. He then used this fact at 51:30. he addressed the solution to this elsewhere in the comments, so i wont mention a workaround. i found one beautiful deduction that simon missed during my solve. it didn't really help with the solve, but i enjoyed it nonetheless. at 42:42, we basically know the composition of purple with respect to parity: there's a 123 or 789 in both renbans of boxes 2 and 4 (so 4 odds and 2 evens), 2 even corners (from the grey squares in boxes 3 and 7) and 2 odd corners in boxes 1 and 9 (all evens are used up in their boxes), and 2 other renbans which have at least 1 of each parity plus 2 unknowns. so in total, we have 8 odds, 6 evens and 2 unknowns. we have to put those 8 odds in grey somewhere, and we only have 8 cells that can be grey. since we knew the parity of so many cells, i decided to color my odds and evens, which let me more easily find the shenanigans in rows/cols 7 and 8

[@NorkasLP]

Oh, another fun one. Will watch the solve tomorrow when it is not way late here.

[@markp7262]

42:45 finish. I decided to stick with the entropy coloring for the whole puzzle, which definitely changed my solve path from Simon's, at least in the middle. Fun fun fun!

[@kimh6979]

Simon is awesome. The videos are awesome. I look forward to them every night. ❤

[@nightflash5951]

I really liked this puzzle because all the rules were familiar. There's too many new things in other ones and then I get stuck on them cause I didn't understand something in them so this was very nice

[@shawncarter7188]

This one looks scary! But then again, they all do. I just like watching the solves.

[@JoRo-hw8dl]

The Eva Green pun made me giggle uncontrollably, thanks for that Simon 😅

[@Zalaniar]

Great video as always! Interestingly, very early on I noticed that once you knew green was 456, the red and blue even squares had to be a 28 "pair". Not sure if that would have mattered in the grand scheme though.

[@David_K_Booth]

Very intriguing puzzle - well done James! Slightly surprised to find that I had beaten Simon's time - that rarely happens.

[@jinkela7295]

10:15 peach line seems to be more appropriate?

[@dariodiluciano9443]

I just randomly picked a CtC video and the intro is "the riding of the rohirrim", how beautiful is this channel?

[@easternbrown]

The deduction Simon makes from 57:35 had been available for some time due to the grey square clue in the box (actually ever since he first found that green was the 456 entropy group given it sees the even digits in the other two groups). However, doing it this way Simon seems to demonstrate that that very clue is unnecessary to find the solution and could have been omitted by James Sinclair.

[@MarushiaDark316]

Love the "Riders of Rohan" intro cover.

[@mekkelino]

Hi, I'm still new to these more sophisticated Sudoku puzzles, so would love to get some clarification on the following. 46:05 Simon argues that since there are (at least) two 2s and 8s in grey, and there are only one of each on the top and left purple line in total, the other two must appear on the right and bottom purple line, hence giving away the numbers for both these lines (without yet knowing which is which). While Simon doesn't immediately use this, he comes back to it later to fill the lines. However, couldn't it be argued that a second 2 and 8 would have also been allowed in the bottom left and top right corners which are also purple, hence not allowing us to determine the numbers on the right and bottom purple lines just yet? Now, I'm sure this can be ruled out somehow but I don't think an explanation was given. So did I misunderstand or simply miss the explanation, or was this an oversight? Thanks!

[@steve470]

This was an oversight. The logic that does prove it is available in replies to other similar comments.

[@mekkelino]

Thank you, much appreciated ​@@steve470

[@stevenape377]

I came here because I was worried about the same thing. Well spotted! :)

[@aralornwolf3140]

"It's a great line and deserves to be repeated." - We Few by David Weber and [Co-Author] The two took his "Riders of Rohan" speech and adapted it to that Sci-Fi setting. "Now For Wrath. Now for Ruin. And a Red Dawn!"

[@markheisler5118]

That Eva Green pun haha😂

[@B1GB1RDB4G3L]

Love you Simon

[@Rach881101]

56:21 for me. Nice puzzle!

[@Paolo_De_Leva]

_"Magnificent puzzle"_ is an understatement‼ This is the most complex and at the same time elegant and brilliant set of interactions between clues that I can remember. Each of them (renbans, nabners, thermos, entropic lines and squares) contributes with some minor restriction. Only when considered together these *weak restrictions* create the *powerful magic* needed to "un-stick" yourself and break-in. _"World class puzzle"_ would be an understatement as well‼ In short, this is definitely a sublime *Cosmic* class artwork. 👏👏👏👏👏👏👏👏👏👏👏👏👏👏👏

[@Paolo_De_Leva]

By the way, I see Simon used *Phistomefel's theorem.* I did not. The *renbans* in boxes *6* and *8* are restricted by the entropic line, and I focused on their combined intractions with thermo and nabner in *box 9.* This magic then progressively ignited the other renbans, thermos, and nabners, and when its fire reached *box 1* in the blink of an eye the puzzle solved itself. _"Sorry, I have got nothing here"_ (Simon @22:07) I guess Phistomefel's theorem was not the only trick required to "un-stick" yourself and break in, and my solve shows it is not even strictly required, but I am glad Simon explained it because I bet it was used by Sinclair to design this masterpiece.

[@Paolo_De_Leva]

This *permuted* version of Phistomefel's theorem can be proved more elegantly without using *overlapping* purple regions. Just compare the following two sets: 1) row 1 + row 9 + box 4 + box 6 2) the four columns containing the nabners (columns 2, 3, 7, 8) Similarly, the *standard* version of Phistomefel's theorem can be proved by comparing: 1) row 3 + row 7 + box 4 + box 6 2) the four columns containing the 2x2 squares (columns 1, 2, 8, 9)

[@Paolo_De_Leva]

Thank you Simon for not explaining the *corollary* of the entropy line definition in the "Rules" chapter, @10:45. 😏👍

[@titusadduxas]

1:25:52 - I was really cjiluffef to have spotted that the remnants in boxes 4 & 8 couldn’t have extreme digits on and furthermore the 1 and 9 couldn’t be in the same boxes in C9 and R9. That got me the 2468 Nabner in box 9. Sadly despite looking at for ages (and not knowing the alternative Phistomofel) I got stuck. Once Simon showed how the other two renbans needed a 1 and 9 on I flew through it.

[@AlphaPizzadog]

18:50 it looks like it's just a variation of phistomefel's ring but using different rows, right?

[@Ray-iu7hg]

28:00 - super fun!

[@RaceMasterDave]

If you select Rows 2-3-7-8 and then Colomns 1-4-5-6-9, then take out Box 5 to bring equality in sets, your set of 4x9 digits has been proven without having to consider corner cells that are counted twice in the perimeter. That makes it easier to understand and less likely to make a mistake with the double counted cells, I found.

[@theredstoneengineer6934]

76:51 for me. That was breathtaking. Just wow.

[@jeremyjorgenson8237]

Even Green! : )

[@liiiinder]

58:00 you could have gotten that 10min earlier when you pencilmarked that the even digits was blue and red, as they both see the square and they have to be 2,8. :)

[@charlieyhp]

Sometimes it is just difficult with color weakness. The 2x2 squares are gold right?

[@shaunbrowne9870]

44:30 The key here is that you already have five odds in purple and need to put in at least three more (renbans in row 9 and column 9 + r9c9 already seeing four evens), which sums to 8, which is all the grey cells you have left. 46:55 The above puts the 8 in box 3 in column 9, so you would know which way around 876 and 234 go now.

[@annesorensen4004]

It is exactly the geeky jokes that would be the best thing at a party 🎉 🤓 yeah I’m also the odd one out at parties 🤭 but I found my true crowd, so being odd among “muggles” doesn’t bother me that much now

[@tessabrisac7423]

About 52:14, I don’t undestand how Simon knows there must be a 2 and an 8 on the remaining Renbans. Could not the 2, the 8, or both be in the corner cells? What did I miss?

[@rickk9897]

Doesn't a 4-pronged namber line have to be either all even or all odd? So there's no way the top right or bottom left one could be 2-4-6-8 because of the square in the corner. Right? Why did it take the solver so long to get there? Or am I missing something?

[@WimmekeVL]

Not sure if that was the trick, but after you explained the sort of phistomefelly going on, It's clear that whatever lies in the corners is designed to exclude 1 and 9. They aren't even and the thermometers both need something higher and something lower. Not sure what to do with that though. If your even digit is 4 or 6, there's no problem slipping a 1 or a 9 in one of the renbans.

[@steveunderwood3683]

Very nice interplay of several standard patterns. Join the dots and it all falls apart.

[@dominikskorjanc]

Why doesnt 1468 work for the nabner lines?

[@jinkela7295]

Before the logic steps, I guessed that the corner cells on the thermo must both be 5's to "keep balance". BUT actually it took me 50 minutes for me to realize that the digit 5 is the key

[@RogueAPBT]

Love the guitar intros. I was a little mesmerized by guitar playing Simon's eyebrows on that one. I might need more caffeine.

[@joekerr3638]

And Rohan will answer!!!

[@diacor4life489]

Thanks for that lovely intro ❤

[@marssang]

Simon if you want to prove the pattern used in this puzzle to the viewers just use C1, C9, B2 and B8 as one set, and R2, R3, R7 and R8 as the other set, and you wont have to double color the corners and explain how you remove just 1 of the doubles. You can also use R1, R9, B4 and B6 as one set vs C2, C3, C7 and C8 as the other set.

[@keyboardegg931]

You can prove that modified Phistomofel theorem more cleanly (not having to double count the corners) if you use row 1, box 4, box 6, and row 9 as one group, then columns 2, 3, 7, and 8 as the other group :D

[@angec9908]

So sad to hear about Bernard Hill

[@chocolateboy300]

I finished in 179 minutes. I have not watched the video yet, but I did not find some easy trick. I think I found fragments of the trick. I first realized that the renbans impact the nabner lines, so the bottom and right renbans were limited. I figured out that they had to be different, only able to share one number at most. This forced 3467 to always appear on either, limiting r9c9 to 258. I, then, figured out that 2 and 8 always broke thanks to both r1c9 and r9c1 impact on box 9. So, 5 must always be in r9c9. From there, I knew that the bottom and right renbans had to be 234 and 678, so I made an illogical step and thought that 678 on the bottom had to be ruled out due to box 7 nabner breaking. This was wrong as I had wrongly assumed that 8 was locked into column 9 and that 2 was locked into row 9 in box 9. This lead to it breaking in box 1, with row 1 and column 1 containing all the digits, leaving r1c1 unable to be placed without breaking from the forced thermo putting too many digits in either row or column 1. I didn't want to start over, so I skimmed the video to see if my renbans were correct and they were not. I tried to see how it went wrong and came up with some other logic on the left and top renbans impacting box 3, 7, and 1. It broke under my previous digits, so I was able to move forward with the correct digits on the bottom and right renbans. After looking for a while, I realized that the left renban could only be 12345, with the 6 being removed due to the bottom renban also having 6, putting strain on box 7. Same for the 4 in the top renban. This lead to me looking at r1c9 and r9c1 and realizing that 8 and 2 break, respectively. This lead to digits bouncing around the grid and finally, the finish where the entropic lines were determined in both cells r3c6 and r6c3. It sucks that I couldn't find the elegant trick and had to treat the puzzle this way. Great Puzzle!

[@Steev42]

I could be wrong here, but I think Simon got lucky on this one. When he was deducing that the renbans in boxes 6 and 8 were 234 and 678, he did it by realizing that there were 2 8s and 2 2s in the purple cells...but at that point, it was possible for the 2nd of each to end up in the box 3 and 7 corners. If that's where they were supposed to be, that would have been an interesting backtrack. As for me, after approaching 3 hours without a digit (even after watching the beginning and getting the phisto variation), I gave up on it. But I had at that point figured out that R4C4 was a mid-entropy even digit. So I'll call it a win.

[@jimi02468]

Interesting to see nabner lines appearing again, the pet peeve of Simon

[@eddieharwood7788]

I think I would have been stuck forever even though I got to identifying that I needed a 234 and a 678 renban using entropy. I had not seen that version of Phistomofel ring before.

[@srwapo]

@52:23, no, it's not clear. Can't the 2 and/or the 8 be in one of the corners? Edit: this is addressed in another comment.

[@57thorns]

57:45 Are you telling us the that evenness of r4c4 was not strictly necessary? Except it did push the 5 into the center.

[@r.b.4009]

To be fair, Eva Green IS quite distracting 😂❤

[@Wakaflockabach]

RIP Bernard Hill... RIP Theoden. "Fear no darkness... TIL DEEEEEAAAAAATH" 😢

[@FantasiA2K]

Rest in Peace Bernard Hill❤

[@angec9908]

Me starting to yell at Simon to check his sudoku

[@TheMinder]

Simon: Oh, I don't know what to do (12th iteration) Audience: SUDOKU!

[@kevray85]

Simon should Goodliffe the evens from the start of the puzzle.

[@JDHutchison]

RIP Bernard Hill

[@tylerhloewen]

Isn't the reasoning At 52:00 wrong, because there could be an 8 in the bottom left corner, and 2 could be in the top right corner and not on the renban lines? This gives enough freedom so that you can't yet determine what is on the remaining renban lines.

[@felicote]

The logic at 46:50 is a bit incomplete. Simon concludes that the second eight and two must be in one of the remaining renbans but he doesn't disprove if they could instead be in the corners. The reason they cannot is that the renbans must have two evens and one odd each and theycant have a 5 since they would break the entropy line. Therefore the second 5 must be in the bottom right corner and the ren ans must be 234 and 678. And they must be different otherwise we end up with 3 of either 2 or 8.

[@W_Qimuel]

The geometric relationship could have been demonstrated more simply by highlighting columns 2, 3, 7 & 8 in one color, and rows 1 & 9 and boxes 4 & 6 in the other color.

[@noahvale2627]

I'd like to team up with Simon, he'll do the hard steps (which are beyond me), and I'll do the easy steps which he overlooks.

[@bobblebardsley]

Even Green would, I presume, be no friend of Oddjob.

[@HunterJE]

The easy way to keep track of the "exploded" versions of phistomefel is the ring its always made up of cells that don't share a column or row with any of the squares...

[@TheCaregiverSITMOB]

nice title

[@LednacekZ]

i realised all the components of your logic. I dont understand the logic of the solve even though you explained it. i am not smart enough for this sudoku.

[@evilkep7390]

He was the captain in Titanic too