Simple Rules Yet Simply Incredible Solution

** TODAY'S PUZZLE **
Yesterday we said Happy Birthday to one of our younger viewers, Ethan - who turned just 8. His favourite sudoku type is killer sudoku and today we hope to make him happy. Jay Dyer's Ravine is as good as it gets - a puzzle that just makes one shake one's head in admiration.
Play it at the link below:
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Rules:
Normal sudoku rules apply. In cages, digits must sum to the small clue in the top left corner of the cage. Digits cannot repeat within a cage.
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As well as the Phistomefel and Jay Dyer extravaganzas, Simon's solve of Magnus Josefsson's new puzzle Castle Wall Yin Yang #1 is now available as a bonus video. You can play the puzzle at the link below (and the logic-masters link contains an example):
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[@jaydyer3999]

Thanks for the solve! Interestingly, you approached the SET in the opening a bit differently from me; I set it with the classic Aad set geometry in mind, but the asymmetric version you used actually made some of the initial logic (especially the 3s and 7s in column 5) a lot easier to see, so it was really cool to see it approached that way.

[@joethornton5321]

I immediately thought of Aad when I saw this puzzle. I really enjoyed solving it. Thank you for sharing it.

[@Pulsar77]

Yes, I used the classic set geometry as well, summing the digits and doing minimum-maximum logic. Simon surprised me here, I didn't see that trick.

[@davidrattner9]

Sublime construction and wonderful use of the AAD geometry. Joy to have featured one of masterpieces on this channel.

[@KyleBaran90]

I'm familiar with the 4x4 and 5x5 set thing, but I don't think I've seen a puzzle combine it (elegantly) from multiple corners. Always thought about that. Good stuff.

[@mattmayoh9680]

I used the classic geometry you had in mind, and thought that made it easier due to maths. The 12 pair are forced in r5 because they're not in the 21 cage, there's a set of 1-7 still to place in r5c1-4 and r1-5c5. 21 cage has either 57 or 67, 67 leaves 1-5 at the top of c5 and a broken 13 cage, so it's 57. Fun puzzle.

[@balkthor]

You gentlemen have been doing this for 3 years (more?), and are still able to clearly explain sudoku tricks from basic to advanced just as perfectly 3 years later. Take a bow.

[@koocnaed]

Cant believe Simon spent 3 mins explaining the X Wing, then 30 seconds later when he placed the first 6 didn't immediately place the other 🤣🤣🤣

[@luiscarlosdelagarzabecerra7373]

And then wrote "26" on R6C2, a yellow square that he highlighted as being unable to be 6 xD

[@olliepeacock]

And he never used the X Wing to place the other 6, instead he did the longest possible way!!

[@sonalita_]

Came here to post the same thing. We surely can’t expect Simon to do Sudoku in a Sudoku puzzle!

[@spatulamahn]

Apparently, Simon expected more than two 6's in those two rows! 🤣🤣

[@werefrogofassyria6609]

It's almost like when he has his cursor exactly where the next step is, and he spends 5 minutes asking where he should be looking. The Werefrog figured it out without the x-wing, but the x-wing was actual logic.

[@trisha2584]

Simon - I got caught singing "there's 3 in the corner" today and got some strange looks plus someone said "you are doing a suduko and watch CTC"- I blame you for the embarrassment but thank you for me meeting a fellow CTC watcher.

[@AndrewHartshorn]

Great solve - I'm glad you said 2 years ago you might not have solved it. Gives us all a tiny amount of hope that maybe in two years we are in with a tiny chance ....

[@michaeljbuckley]

Love how Simon takes the time to explain concepts. Breaks it down to simple components. 💪

[@matthewgiallourakis7645]

I am honestly shocked with how much symmetry is in this puzzle and yet the center turned out to not be a 5.

[@DonaldSjervenE]

Curiously I was skeptical of it being a 5. A 4 or 6 maybe. Adding corresponding boxes disrupts the notion of symmetry. e.g. 9+24=33 while some other sums are multiples of 10 like 28+42=70.

[@PaulAndHisUkulele]

I found this solve to be monumentally difficult and resorted to a lot of “what if it’s this???” guesswork. Huge props to Simon for this and explaining the logic of the Scrabble Tile Bags so eloquently

[@SourceOfBeing]

"I can see the red against the purple" _Highlights cells that are green and pink_

[@MadsOcto7]

Yeah 😝

[@t-w-n]

he's colourblind though, isn't he? Seems to be red green blindness

[@MadsOcto7]

@@t-w-n yeah; I don't know if he's colourblind, but I vaguely remember him saying he was. He did correctly identify the colour as green both before and after though.

[@TracyCarolan]

Simon, your explanation in the beginning with the Scrabble bags of numbers shows what an astonishingly gifted teacher you are. Well done!

[@kathyjohnson2043]

Econ students should have had him for a teacher, but we get him instead 👍

[@Roblilley999]

Whilst doing my Nuclear physics homework, whilst watching the video knowing that 12 is bigger than 9 stopped me making a stupid mistake and making the world spin backwards

[@pg5200]

What a wonderful puzzle. Took me 1h22 plus I needed the nudge about set theory and which sets to opt for, otherwise I was stuck. Absolutely great, many thanks to Jay Dyer and to you Simon for sharing !

[@atlhunt47]

I sat looking at this puzzle this morning attempting to use set theory in some way, failed, and ended up solving the puzzle using other methods...only to find out this was todays video and Simon was able to show me where I could have used set! I love when this happens :)

[@emilywilliams3237]

It was nice to hear a SET explanation again - I realize that I have missed some puzzles over the past several weeks (holidays getting in the way of watching CtC *gasp*), but I don't think I've had the pleasure of listening to you explain that for quite some time. Lovely puzzle and solve, Simon.

[@kingofbritons]

So I have seen multiple videos featuring the Orange and Blue bags. What the universe begs to know is how many tiles are actually in Simon's Scrabble bags since they seem to change at random depending on the puzzle. It's like a Schrödinger's bag. There may be tiles that exist in the bag, but we don't know what they are.

[@J3ff_K1ng]

The trick he does at 21:43 I thought of do it but in a different way instead of rotate the original figure create a new one that add 1 row to orange and 1 column to blue which ends in the same thing and I found it really interesting

[@sonaru4]

It's become a habit of mine now to start solving the puzzle while Simon goes through the introductions, and usually by the time he gets to solving I've gotten hard stuck on something. Feel like I'm slowly getting better at solving these kinds of puzzles, but the small things still stump me. Set really helped me, managed to finish just under 38 minutes and would have been at least an hour with out it I'm sure.

[@th.nd.r]

Things I loved about this video: - a 3 in the corner - the beauty that comes from Simon solving a Jay Dyer puzzle - the symmetrical logic - the use of SET - the clever deductions - the word “splendiferousness” Great setting and solving once again!

[@MartinFindon]

Set theory, x wing and a 3in the corner, a CTC classic.

[@amoswittenbergsmusings]

Set logic set logic Cages with totals that Mini- or maximise Outies elsewhere. Normal sudoku rules Supersensational Puzzle from Jay Dyer Worth a fanfare.

[@davidrattner9]

More brilliance from you!!

[@kwongshuchung]

Set theory is always a big barrier for me to break in the puzzles...... The puzzle does have brilliant settings and nice way to solution

[@feliomichaels]

40:xx I have to say I deeply enjoyed the Starcraft video, and it was quite fun. This one was nice, though I sometimes struggle with spotting SET. :D

[@inspiringsand123]

Rules: 05:15 Let's Get Cracking: 05:57 Simon's time: 51m19s Puzzle Solved: 57:16 What about this video's Top Tier Simarkisms?! The Secret: 8x (02:38, 06:49, 06:51, 06:54, 06:54, 07:03, 07:04, 07:22) Bobbins: 3x (03:25, 24:32, 32:56) Three In the Corner: 3x (31:16, 54:27, 58:11) Knowledge Bomb: 1x (23:35) And how about this video's Simarkisms?! By Sudoku: 16x (32:33, 37:34, 37:43, 38:47, 39:45, 40:54, 41:07, 42:40, 42:46, 43:50, 45:38, 48:09, 54:45, 54:51, 55:47, 56:47) Ah: 11x (22:06, 22:46, 23:05, 26:26, 30:23, 35:21, 37:09, 47:17, 49:46, 50:37, 55:31) Symmetry: 9x (09:19, 18:29, 22:57, 23:07, 28:43, 35:36, 44:29, 47:05, 47:05) Sorry: 7x (16:53, 22:34, 28:04, 29:59, 35:24, 44:01, 55:15) In Fact: 7x (10:27, 11:38, 16:58, 24:08, 36:51, 36:51, 41:21) Scrabble Tiles: 7x (12:04, 12:08, 12:16, 12:19, 12:40, 13:05, 25:19) Pencil Mark/mark: 7x (19:11, 34:12, 41:56, 53:53, 54:18, 54:59, 56:12) Hang On: 6x (18:24, 23:05, 26:42, 30:25, 43:07, 56:40) Beautiful: 4x (25:03, 25:05, 47:17, 54:18) Good Grief: 3x (28:04, 40:02, 50:37) Facetious: 3x (51:56, 51:58, 52:03) Obviously: 3x (05:42, 13:53, 18:49) Clever: 2x (27:32, 56:17) Lovely: 2x (38:33, 47:32) Incredible: 2x (00:36, 00:36) Elegant: 2x (57:38, 57:47) Gorgeous: 2x (57:57, 58:00) Surely: 2x (20:36, 27:43) Snake: 2x (02:38, 02:38) Cake!: 2x (03:58, 04:03) What on Earth: 1x (49:26) Eyes are Drawn: 1x (06:00) Apologies: 1x (10:56) Naked Single: 1x (54:07) The Answer is: 1x (47:23) Out of Nowhere: 1x (53:09) Nonsense: 1x (55:54) In the Spotlight: 1x (54:30) I Have no Clue: 1x (47:26) Brilliant: 1x (36:53) Fascinating: 1x (54:04) First Digit: 1x (40:25) Stunning: 1x (47:19) Whoopsie: 1x (21:01) Phone is Buzzing: 1x (20:43) Progress: 1x (24:42) Wow: 1x (24:39) Fabulous: 1x (57:18) Most popular number(>9), digit and colour this video: Twenty Eight (14 mentions) One (117 mentions) Blue (24 mentions) Antithesis Battles: High (8) - Low (2) Row (19) - Column (15) 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!

[@samlight1387]

How you post this a minute after the video is released lol

[@highpath4776]

Glasses (normally its Glasses on, Begin - or variation, but he did not do a specs check and called for correct glasses to himself)

[@fluffycritter]

Just like High Path I came here specifically to say that there needs to be something for "glasses," possibly specifically "the right glasses" since it seems like Simon is often not wearing the right ones!

[@ThePall91]

no bobbins

[@blakerobinson4198]

the x wing was not obvious, and I think it was the only way to solve the puzzle. I got entirely stuck and had to pause my solve and watch your video to figure it out. Thanks for the great solve Simon. This puzzle was brutal (in a great way), the break in logic was way out of my league, but once I knew how to look at it, I was able to finish the solve (until I got stuck by the x wing).

[@markbennet9058]

Jay's solution videos are extraordinary ...

[@markjacobs1086]

I love how the tone of the colours the scrabble bags have match (very closely) with the colours Simon uses for this example. 😁

[@chironchangnoi]

That's no coincidence; a viewer made them for him based on that colour palette.

[@yaboyJJJJJ]

at about 30 minutes Simon forgets the thing he proved multiple times over already. He proves pink and green are the exact same digits. So when he wrote 567 as options for green he could immediately make the 4 pink digits on the left 56789. same on the blue and orange regions. Once you have 345 on blue the four orange rightmost digits become 12345

[@maxentius681]

The only piece of interesting logic that I think Simon missed was being able to resolve the Set's via min's and maxes in the 13 and 21 cages respectively.

[@yaboyJJJJJ]

at 32 mins in I'm screaming at him foe considering a 4 in the pink region on the left even tho that's impossible because that would mean 2 fours in the green region due to logic he proved multiple times already.

[@awebmate]

That is the only piece needed. Knowing that r6-9 c5 adds up to 14 more than r5 c1-4 was my break-in, and that was enough to solve everything.

[@markp7262]

31:07 finish. I just SAW the logic on this one. I used the modified set 4x4 vs 5x5 on each corner one at a time (upper left 4x4 has the same digits as bottom right 5x5 minus box 9, then reverse it). When Simon did the X-wing on 6s, I actually did a bent X-wing using box 9 and the 28 cage instead. This gave me the 3 in r8c8, which helped in a few places. The bent X-wing also allowed me to remove 6 from the rest of the 28 cage, giving me a second X-wing in rows 7 & 9, and placing the 6 in box 7. Amazing puzzle!

[@emmbeesea]

If I may give a bit of feedback, as someone who is color deficient, I was struggling to see the green/orange overlap and the blue/purple overlap without looking really close. Would've preferred blue/green overlap and orange/purple overlap for easier distinction, but I also know that in heat of the moment in a live recorded solve, it may not always cross the mind. Just something to perhaps consider for accessibility. Still, fantastic solve, Simon! Cheers!

[@emilywilliams3237]

So interesting! In many puzzles where Simon or Mark use colors, viewers comment about whether the colors are suitable for color deficient people - and the answers are all over the map. They have said that their feedback overwhelmingly prefers the blue and orange (the lighter shade of each, the colors that match the scrabble tile bags) as being the least similar among those available in their original palette. The other colors are newer, so maybe those have not been fully commented upon - but it seems that color deficiency comes in many different varieties.

[@aidarosullivan5269]

Yeah, the blue/purple combination is probably the worst (and I don't even have that particular type of color blindness)

[@victoriam6569]

What a brilliant solve! :)

[@minamagdy4126]

I remember long ago, maybe even 2020, there was a puzzle that used the same SET equivalence as this puzzle as part of the ruleset. As it turned out later, that rule wasn't needed, as it just so happens to be consistent with regular sudoku. Really neat to find a puzzle where all of the important steps come from the interaction between killer cages and this SET equivalence.

[@mattmayoh9680]

Aad van de Wetering has been mentioned a couple of times as noticing that particular equivalence and using it in a couple of puzzles.

[@Kinada]

The thing that I remember from the original puzzle that highlighted this logic and it's followups is that the cells that make up the 42 cage and the 9 cells that surround it through boxes 2-4-5 will always contain the digits 1-9 once each PLUS the digits that exist in the 28 cage on the other side. That logic can be inverted so that the 28 cage and the cells surrounding it must contain the digits 1-9 once each and the cells that make up the 42 cage. This means that the 28 cage side must contain two sets of the digits 8 and 9 without putting them in the 28 cage and the 42 cage must contain two sets of the digits 1 and 2 without putting them in the 42 cage.

[@longwaytotipperary]

❤ the logic and always ❤️scrabble tiles!

[@davidrattner9]

Love your uses of ❤ and love that you love scrabble tiles!! Board game night? 😄

[@amoswittenbergsmusings]

@@davidrattner9 I ❤the ❤ly 🎵of her comments and the unfailing friendly 🎵of yours. Welcome to the mutual affection society.

[@davidrattner9]

@myverypersonalstuff Absolutely wonderful from you Amos with what you did. Brought a huge smile to me. The mutual affection society is a honor to be a part of. 😁

[@longwaytotipperary]

@@davidrattner9 I do ❤️scrabble! 😊

[@longwaytotipperary]

@@amoswittenbergsmusings Amos & @David Rattner ❤️being in mutual affection society with both of you! 💕💕

[@srwapo]

77:27 with a lot of help. I figured out the digits in Row 5 and Column 5, but needed help in a bunch of other spots. The worst was penciling 89 pairs in every box and forgetting to use the 21 Cage in Box 4 to figure out which one was the 9, d'oh!

[@tat2dgerl]

Aww ty Simon! I was flying on my birthday so took me a bit to catch up on the missed days. Chris still owes me chocolate cake though 😂😂🎉🎉🎉🎉

[@DerMarkus1982]

12:00 Oh, look! A complete bag set of Simon Anthony's *Phistomefel's Theorem / Aad Van De Wetering's Theorem* Illustrative Scrabble Tiles (they seem to be multi-functional 😁) ! That's Bobbins!

[@NaHBrO733]

After the initial color hint, I got all the way, stuck at the last bit, the x-wing is spectacular! I couldn't find it at all.

[@wpuymac]

Awesome!

[@Coyotek4]

32:26 ... my best solve of a 'Simon' video in some time, I think Nice puzzle!

[@jasonmetcalfe4695]

Thats a great killer puzzle, I'm getting better at them I spotted the central 6 before Simon removed the colours

[@kuraban1]

Would love to see links to the LMD pages for these puzzles (if they are up over there).

[@Mitrasmit]

* adds colours to show x-wing on 6's * * doesn't use X-wing to find 6's *

[@ericpraline1302]

I usually struggle with SET because I can never find the right ones, but it was pretty well telegraphed here. Like Simon I'm not overly keen on lots of pencil marking, but for this puzzle I doubt I could have solved it without heavy marking. I did not spot the x-wing.

[@praematura]

1:00:41 for me, but I will admit I missed some obvious things along the way that made my solve much harder, and did need to bifurcate a bit right near the end. I noted my initial solve path was very similar to Simon's, then he noticed things I didn't and we diverged a fair amount. Still an amazing puzzle!

[@ServantOfSatania]

60:30 This was a very clever puzzle;

[@haniapopowska8966]

"Which is not, perhaps, the most unintelligent thought I've ever had" How to say something simple in a complicated way 😆

[@Donquity]

that was so much fun

[@christophneuwirt7433]

This may seem like an odd question to ask. But how can I change my color palette (like seen in various other videos) so that I don't have to stick to the nine "pre-installed" colors? And another question while I'm at it - how can i mark cells with letters? Thank you in advance!

[@Rach881101]

48:28 for me. Fantastic puzzle!

[@eckberthighwater2555]

Does Simon not use the fact that the difference between 42 and 28 is 14 to help with the 9/15 cages?

[@MaierFlorian]

When you want to hit the like button at the end of the video and find out you already did during the video :'D

[@shadeblackwolf1508]

I found that with the bigger setup, 4x4 against 5x5, there is a massive tension on the center tile, which was my break-in

[@Swisswavey]

Wow. That took me an hour and three quarters. I think that was just a fraction too difficult for me. Happy to finish it though.

[@OnAFitnessJourney]

Extremely happy to solve it in 51:00 mins :)

[@jimi02468]

The "cage total tables" found from killer sudoku Wikipedia page is pretty helpful. I hope using them doesn't count as cheating.

[@MisterM2402]

If you go to Settings on the puzzle page (cog icon), under Advanced you can turn on "Killer Calculator". Each time you highlight a cell in a killer cage, there's a dropdown box above the puzzle title that shows all the valid killer sums for that cage. It's super handy!

[@BryanLu0]

As long as you find the puzzle enjoyable who's to restrict what tools you use? (Unless you're in a competition type setting)

[@jimi02468]

@@BryanLu0 Yeah I think if tools allow you to simply to something faster that you could have done anyway without tools, it doesn't count as cheating. Even in some sort of competition. You could memorize all the cage totals and instantly know them but that wouldn't make you a better sudoku solver.

[@RichSmith77]

​@@jimi02468 Counterpoint: I'd argue, yes, it would make you a better sudoku solver. It's just not essential for a casual, recreational solver.

[@jimi02468]

@@RichSmith77 Well, I would say that the time it takes to finish a sudoku is a poor way to measure how good you are at sudoku. A better way to measure it would be to see how difficult puzzles you can even solve in the first place. I mean, someone solving the most difficult puzzle in eight hours is way more impressive than someone solving a mundane killer sudoku in record time. Even in a math exam in high school you are allowed to use a calculator, why? Because basic arithmetic doesn't make you good at math unless you're in the first grade. For a similar reason using the killer sudoku calculator should be allowed in a sudoku competition.

[@l3afman]

21:18 "the red against the purple" Simon I might be wrong but that looks like green to me... 😅

[@DarrenNakamura]

Got it in 97:35. Was stuck for a while before I noticed that 57 pair in row 1.

[@timcotton1782]

42-28=14. Ergo, the orange cells R1234C5 must be 14 less than the blue cells R5C6789. Given the restrictions created by the 15 cage and 9 cage, these values must be 10 in orange and 24 in blue. The blue cells are forced to be 1234, and the orange cells are an 89 pair and a pair adding to 7. Using the extreme digit in either cage (9 in the 15 cage, 1 in the 9 cage) breaks the puzzle in Box5, so the orange cells in Col5 read downward as a 34 pair and a 12 pair, the blue cells in Row5 read right to left as a 34 pair and an 89 pair.

[@RichSmith77]

Why not 11 in orange and 25 (8+9+(8)) in blue? (I think you have blue and orange the wrong way round when saying "blue cells are forced to be 1234”).

[@ajjeff1033]

The 6... the X-wing you pointed out and then ignored... the bloody 6.

[@johnh9749]

Simon's break-in is unbelievably elegant, but there is a much simpler way in. Basic maths shows that the 9 squares immediately outside the 42 cage sum to 31 (r5c1-r5c4 and the first five digits in column 5). But r5c1 + r5c2 cannot be less than 12 and the first five digits of column 5 cannot sum to 15 because of the 13 cage at the bottom. So have to be 1,2,3, 4 and 6. Rest of the solution follows.

[@OldBounder]

That's the break-in I found, much more powerful.

[@kingme5167]

Please explain how you know those cells sum to 31

[@RichSmith77]

​@@kingme5167 The only way I can come up with a formula to get the total 31 is to divide the grid into similar areas as used by Simon to prove the set relationship. Highlight the left most five columns, and the bottom most four rows. Let the overlap be A and let the region we're interested in (the nine cells in the L outside the 42 cage) be X. From the five columns, 5 x 45 (5 columns) = 45 (box 1) + 42 + X + A. From the bottom four rows, 4 x 45 (4 rows) = 45 (box 9) + 28 + A. Subtracting one from the other, 45 = 42 + X - 28. So X = 45 - 42 + 28 = 31. I don't know if there's a more straightforward way to reach that calculation. How just knowing that the sum of those nine cells is 31 is more powerful than knowing those nine cells are exactly {1,1,2,2,3,4,5,6,7} (sum = 31) that SET gives you, I'm not entirely sure. 🤔

[@mattmayoh9680]

I'm curious what the 'basic maths' you're talking about is, too. Yes, it's easy enough to show those digits add to 45-42+28 = 31, and likewise the digits immediately outside the 28 cage add to 45-28+42 = 59. But the only way I can see to show that is to use set theory, and by doing so I know the exact digits. The 2nd part of the breakin could be done much faster once you know that first group of 9 adds to 31/contains exactly 1-7 + 1 & 2 (min of r5 c1-4 is 15 due to the 21 cage, min of r1-5c5 is 16 due to the 13 cage, so they're forced, now 1257 in c5 forces 34 into the 9 cage and puts 6 in the centre), but I don't see a faster way to discover what that first group is/sums to. Can you please elaborate on your simpler way to find that?

[@mattmayoh9680]

I hadn't watched that part of the video, I assumed Simon used the same sets as me, but he didn't. I think the breakin is more obvious if instead of orange being r1-4, it is instead box 2 & 3, r45, so I suspect that's what you meant. It's not 'basic maths', it's just a slightly different choice of set.

[@terrencemoore4918]

27:17 Everything seemed obvious and ordered to me. Since I"m usually near video time to 20% over, I will be curious to see where the slow part was and when I'm supposed to shout at Simon.

[@RoderickEtheria]

51:24 is an x- wing on 6s between c3 and c9.

[@tzisorey]

A Sudoku coloured like a game of Ludo.

[@hockeyhacker97]

24:45... Wouldn't you use it by now knowing the two mystery digits left in your yellows have to be either a 3/4 or 3/5 because of the 11 digits in both you already have 9 known of the set 1-9 which makes your last 2 numbers (which just happen to fill that 9 cage) the same 2 numbers as your 2 remaining cells in yellow... I am guessing you have to do those 4 row/column things in all 4 ways, but while that doesn't give you any set number it does make that 15 that much harder to fill since those 4 cells are 1,2,3 and then either 4 or 5 so you know a 4 or a 5 goes into the 15 so no matter what in the uncolored part of the 15 only 7, 8, or 9 can go in it because even if you go 5, if you try to do 6 the largest you could make it is 6/5/3 which does not add up to 15.

[@jonathanallan5007]

@21:15 Oh no, Simon sees red.

[@l3igl2eaper]

Aww I missed the X-Wing on sixes. Instead I found an empty rectangle on sixes that eliminated two 6 pencil marks from Box 4 to complete my solve. Darn! Could've done it faster.

[@crossgibson6986]

love everything about this channel but my only qualm is that i have to skip a whole minute of video everytime simon mentions “the secret”

[@bezowee]

You will grow to waiting for it

[@yaboyJJJJJ]

yeah it's a double edged sword. him being so sweet and gentle is how so many of us got interested in sudoku and this channel, but after watching a while it feels like being treated as a kindergartener.

[@amoswittenbergsmusings]

@@yaboyJJJJJ " it feels like being treated as a kindergartener": don't you just love it?? Rituals have this effect on me - YMMV

[@_-_-Sipita-_-_]

59:29 for me. got stuck for long at what looks like 44:36. but doing the guessing game was not worth it and i had to guess that.

[@KJ07]

I have seen this sudoku before…even Simon changing his glasses….is this déjà vu or am I hallucinating or is it really a re-upload ??

[@donaldsnyder1543]

Simon uncolored the grid , has he been replaced by AI?

[@robbrown5158]

You'll always remember reveen.

[@hamishwatt2475]

Raced through the start and thought I was on to beat Simon's time but totally missed the x wing on 6s resulting in a DNF (finishing after cheating by watching the video)

[@annoxistenebrarum4596]

53:14 "And it is probably gonna do nothing". In the category of sentences that aged like milk...

[@Shippochi]

A great solve for learning useful tricks! We had set theory (helpfully explained with the bags of scrabble tiles), an X wing, and of course our favorite secret about the number 45!

[@miriamberg3948]

And a three in the corner 😄

[@forgottenfamily]

Got everything but the X-wing, dangit.

[@CrankyOtter]

c5r1,2 = r5c8,9, which has to be 1 or 2 less than 9.

[@MadTamB]

Still trying to solve it. But I broke in using maths.you've got a 13 & a 28 cage and a 21 & 42 cage and then looked at the differences.

[@ndkndlvlsvls]

Can someone please set a puzzle with an x-swing of threes in the corners? I need it okay 😄

[@ndkndlvlsvls]

I giggle every time we get the song

[@darci4434]

I wonder if he will talk about 45 rule

[@Roblilley999]

What's this 45 rule?

[@TheSonicPerson]

@@Roblilley999 every row column and box sums to 45 because they contain all the digits from 1 to 9 exactly once each

[@darci4434]

@The Sonic Person correct I said that cos everytime he talk about 45 rule he always say I only tell this to favourite people 🤣

[@Aoderic]

Shush! 🤫it's a secret 🤐 only Simon is allowed to reveal it 🤭

[@darci4434]

@@Aoderic true

[@kingme5167]

This one frustrated me greatly. I never notice set theory unless I have no other way in at the start. Never think of set partway through. I was able to place many 789 locations using the 24 cage and various geometry tricks, but the symmetrical 9 cage was much less helpful for 123s so I eventually got completely stuck and gave up.

[@TurquoizeGoldscraper]

76:42 for me.

[@gtieddy6065]

Takes me an hour to do grandmaster on Microsoft Sudoku let alone the stuff you do lol.. I only know the basics though.

[@briangarrett2427]

I'm watching a chap who says "whoopsie".

[@TheEricthefruitbat]

Can't believe Simon is continually astonished by the obvious symmetry.

[@sake9164]

Early 'gangers', assemble.

[@justinfarmer8371]

Points out the 6 x wing then doesn’t use later on in the puzzle 😂

[@theredstoneengineer6934]

79:58 for me

[@CowCommando]

The 28 and 42 cages look familiar. Hasn't he solved this one before?

[@robertcousins2274]

31:14

[@RealCadde]

44:44 "What can we say about ones? Nothing..." INCORRECT, maybe not helpful but still very incorrect. In box one, 1's are limited to three places, R2C2, R3C1 and R3C2. This gives you an X-Wing on 1's in rows two and three so there's 1's in row one of box three. You can do the same thing on the vertical with 2's. And you have a missing pencil mark for 2's in box three. Witch is pivotal to the perceived 1-2 pair in the 28 cage. In box one you also most definitely have a 7 on the rising diagonal. Along with either a 1 or a 2, as you can't have both 1 and 2 in the nine cage. The last digit in the rising diagonal of box one is a 4 or a 5 depending on the composition of the nine cage. I also think the whole puzzle hinges on the nine cage in box one with a slight possibility that the corner cells of box five having an incompatible composition. ... In fact, i thought about it and came to the conclusion that no matter what the nine cage in box one is, coupled with the placement of 1's and 2's in box three and box seven literally ALWAYS forces R6C7 and/or R7C6 to be a 1 or 2 respectively. My mind is not capable of keeping track of everything that happens depending on where 1's and 2's go in box one but the end effect is that it affects the 1's and 2's such that those two cells in the 28 cage always turns a 1 or 2. And so, now you just have to figure out where 3-4 and 5-7 goes in that cage. My presumption is that R8C6 will be a 4. Also, on a side note, R4C7 is a 5 or a 6 by sudoku. It's twin exists in R7C4 and is a 3, 4 or 6. One of them will have to be a 6.

[@grrr_lef]

Tell me you're color blind without saying you're color blind: "I can see the red against the purple very naturally".

[@achad1607]

I solved it without using set theory. It was a very long and hard slog.

[@Gonzalo_Garcia_]

17:40 for me. I immediately saw the break-in on this one and didn't get stuck at any point during the solve. Fantastic puzzle, I really really enjoyed it!

[@ElCheezus]

"What does that 6 do? Probably nothing" he says. Those of us who see how long is left in the video know better.

[@JimKirk621]

how come it said " the puzzle doesn't contain solution "? I get this when I try to solve it too.

[@stevepinard5826]

Apparently, there's a means for the puzzle setter to provide the correct solution to a puzzle (perhaps the ones derived from f-puzzles). Sven's software may not know all the rules, so it can only check the constraints it knows about. For example, in this puzzle it is merely telling you that your solution meets the normal Sudoku and killer cage constraints. It does not know about potentially other rules, so does not know whether there are multiple solutions that meet those constraints. (I feel like I'm doing a horrible job of articulating this).

[@wanderlustwarrior]

1:20:19 Jeez, that was really hard for me.

[@wanderlustwarrior]

Next attempt, I was making great time and almost got it in 45 minutes, but made an error that I couldn't spot until far too late, costing me the solve.

[@bobfish7699]

Just for fun Simon should be banned from colouring for a week to see if it stops distracting him. He went on a 5 minute explanation of X-wings near the end, using colours, just to show how 6 is limited. And then 2 minutes later he places a 6 and utterly fails to put the other one in, even pencil marking it after a couple of minutes with the left over digits. I am convinced colours put him off....

[@BorisHorvath]

its symetrical sudoku all the way, but simon in his own way refuse to use it

[@johnsouza4391]

Never understand how you can solve the hardest parts then not use basic elimination in rows and columns to reduce your sets. Look in column 9 and 1 after set. Oh, I see you found it.