Math Professor Sets Impossible Sudoku

[@JayBea]

Oh. My. God. I solved this puzzle on my own. I feel like I have crossed a major threshold in my Sudoku journey. I usually don't bother to attempt a puzzle if Simon's video is over 50 minutes, but this time it looked fun so I tried it to see how far I could get, and I solved it! Never mind how long it took, I feel so good! Thank you to everyone involved, truly.

[@nagualdesign]

Very impressive. Well done, Jay.

[@sjm6280]

It's curious when you feel deep appreciation towards people you have never met Happy birthday, Simon, and thank you

[@CrackingTheCryptic]

Thanks so much S J M, really appreciated :)

[@littleviatrix]

Happy birthday Simon! Watching you solve is always such a joy. I wish you ALL the cake you might want today!! 🎉

[@samplename5159]

1:05:55 "this is one of the best puzzles... well, i think we'll just leave it there - this is one of the best puzzles" i had no words to describe it myself, that is exactly how i feel about it

[@XdivineExp]

I love when puzzles don't give up until the very end, and this one truly did put up a fight until the very end. Also happy birthday Simon :D

[@felix_irgendwas]

That r9c5 cell was the most beautiful finish I've ever seen. It is amazing how it is not of any use for the whole Sudoku part of the puzzle, yet brilliantly disambiguates the final cage, while not interfering with any other logic throughoutnthe solve. I don't think Simon could wish for any more beautiful Sudoku logic present. Happy Birthday!

[@zzzanimal1722]

i know i am commenting on a year old post, but figured I would share. I got to this video from watching the video of the setter making this puzzle. And the crazy thing is that r9c5 cell was an accident. he spent all that time setting it, and realized he couldn't finish the puzzle without adding in a rule just calling that cell out. and he was bummed by it. but i agree, it ended up being beautiful!

[@yerel_nimni_avni]

Happy birthday Simon, I hope you had a large piece of cake.

[@gauravmitra150]

Before I watch the video let me say a very happy birthday to Simon Anthony, who gives us all a lot of joy and to some of us also calm us. And I hope he celebrates this special day with a lot of good cake!

[@inspiringsand123]

Rules: 02:26 Let's Get Cracking: 06:11 Simon's time: 1h36m13s Puzzle Solved: 1:42:24 What about this video's Top Tier Simarkisms?! The Secret: 4x (01:29, 14:32, 14:36, 49:45) Bobbins: 1x (03:01) Knowledge Bomb: 1x (50:06) Phistomefel: 1x (16:28) And how about this video's Simarkisms?! Ah: 35x (00:34, 09:51, 14:14, 18:42, 18:45, 18:47, 19:15, 20:20, 21:17, 26:02, 26:04, 28:24, 28:52, 34:09, 34:10, 42:26, 46:58, 48:41, 51:38, 51:56, 55:25, 55:47, 55:50, 58:43, 1:02:43, 1:02:49, 1:03:32, 1:05:54, 1:08:00, 1:08:46, 1:15:03, 1:15:28, 1:15:28, 1:20:43, 1:28:38) Sorry: 12x (06:56, 17:14, 17:16, 18:47, 19:53, 27:01, 28:06, 44:40, 1:18:15, 1:29:30, 1:29:32, 1:29:35) By Sudoku: 9x (21:58, 52:33, 1:02:03, 1:02:08, 1:15:35, 1:19:20, 1:19:36, 1:24:12, 1:28:53) In Fact: 8x (02:41, 12:57, 38:42, 43:48, 55:08, 58:11, 1:14:23, 1:16:54) Beautiful: 7x (19:45, 19:45, 23:25, 38:44, 1:00:05, 1:41:15, 1:41:39) Hang On: 7x (18:05, 41:16, 1:02:49, 1:12:27, 1:30:52, 1:30:54, 1:35:27) Good Grief: 5x (1:16:07, 1:18:03, 1:23:34, 1:26:59, 1:39:53) Clever: 5x (32:29, 39:54, 39:57, 1:40:16, 1:41:20) Lovely: 5x (24:50, 25:03, 28:55, 1:40:31, 1:40:33) Obviously: 5x (23:47, 45:42, 1:10:05, 1:11:46, 1:17:53) Pencil Mark/mark: 5x (33:26, 59:33, 1:19:57, 1:20:47, 1:23:47) The Answer is: 4x (24:03, 31:19, 1:15:58, 1:40:00) Extraordinary: 3x (00:28, 05:41, 1:13:41) Magnificent: 3x (06:06, 1:42:37, 1:42:37) I've Got It!: 3x (51:56, 51:56, 1:29:28) Wow: 3x (05:01, 1:23:40, 1:23:41) What Does This Mean?: 3x (25:17, 31:11, 34:30) Bother: 2x (28:25, 1:12:52) Horrible Feeling: 2x (1:09:57, 1:29:25) Deadly Pattern: 2x (1:29:05, 1:29:53) Surely: 2x (15:31, 50:25) Phone is Buzzing: 2x (47:00, 1:19:00) Progress: 2x (1:01:24, 1:01:27) What on Earth: 1x (1:36:20) Diddly Squat: 1x (1:22:15) Useless: 1x (07:08) Goodness: 1x (59:03) Naked Single: 1x (1:15:19) Nonsense: 1x (1:07:21) Missing Something: 1x (50:09) I Have no Clue: 1x (16:33) Brilliant: 1x (47:15) Gorgeous: 1x (1:41:29) Take a Bow: 1x (1:43:12) Outfoxing: 1x (1:13:02) Disappointing: 1x (1:20:43) Stunning: 1x (1:41:41) Propitious: 1x (1:09:59) Fabulous: 1x (1:41:45) Have a Think: 1x (1:24:59) Nature: 1x (46:01) Cake!: 1x (01:11) Most popular number(>9), digit and colour this video: Twenty (36 mentions) Two (149 mentions) Red (71 mentions) Antithesis Battles: Low (4) - High (3) Even (12) - Odd (5) Higher (2) - Lower (0) Outside (2) - Inside (0) White (40) - Black (35) Column (19) - Row (9) 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!

[@highpath4776]

(Awarded The) Mantle (Of)

[@crashtextdummie]

Happy birthday, Simon! This gorgeous puzzle had absolutely magical flow. No individual deduction was overwhelmingly difficult, but most required at least a bit of thought and there were a lot of deductions to be made. Definitely a highlight on this channel, zetamath has done himself proud again.

[@markp7262]

1:18:47 finish. I went into spurts on this one, flying through portions and snail-crawling by others. I love how it ended with a deadly pattern resolved by the cages. Excellent as always! And Happy Belated Birthday Simon!

[@understoodish]

I sometimes manage to spot something shortly before you do, but I'm amazed by how often you reach the same conclusion from a completely different direction. Your solves are a joy to watch, and I hope you have had an excellent birthday.

[@gameglitcher]

1:05:03 I was looking at the Black dot daisy chain across the top forcing a G20-O10-Y20-B(+/-1) and it would need to link between Green(20)and blue(19/21) with a white dot. Yellow touches green - Blue cannot.

[@crystalgehrt8861]

Zetamath is a genius. I was a little worried at the beginning and a little more worried at the end, but it was well telegraphed and just a brilliant solve. Thanks to Zetamath and thanks to Simon!

[@stumbling]

Zetamath has definitely entered the S tier of setters.

[@zetamathdoespuzzles]

Why thank you!

[@th.nd.r]

That is stunningly beautiful. zetamath has set an absolute hall of famer here, great solve by Simon as well!!! Happy birthday Simon, have a couple slices of your favorite flavor of cake!!

[@dwebb2805]

i recall when simon was putting the 13 cage in row 7 that it was remarkable that you could even put that piece of logic into a puzzle that deep in. somehow it kept on giving even after that! zetamath you have certainly outdone yourself here, absolutely amazing! and of course happy birthday to simon, you give us all a gift every day with your solving and the joy you exude!

[@Shin-no-Ken]

Normally I don't attempt puzzles this hard, because any time I have in the past I've needed several hints (from these videos, usually) to get to the solution-- This is the first time I've managed to solve a puzzle that took more than 30 minutes to solve in the video, all on my own! It still took me all day (off and on, probably around a 2hr 30min solve in total), but it really was a great puzzle and never managed to stump me, so there may even be an argument that it's approachable despite the intimidating appearance.

[@Samish30]

Well I had managed to finish a puzzle faster than Simon a few times but that is definitely the first time I ever finish a puzzle BEFORE Simon actually finishes it overseas 😁 took me 71mn, a bit more than 20 ! Absolutely enjoyed it

[@distortedilluminations1328]

This is tied for my favorite solve of yours (The other one being Chaotic Wrogn by under). That finish was what really pushed it over the edge for me, I adored it.

[@AdventCloudStrife]

The simplicity of miracle type sudokus get a lot of attention, but my goodness this is insanely well constructed.

[@soyazhek]

Happy birthday Simon! You are a joy to watch everyday.

[@CrackingTheCryptic]

Hi Soyazhe, Thanks so much for the kind words and the donation!

[@sgroom8137]

Happy Birthday Simon - thank you for bringing us joy every day. Time for Cake !

[@CrackingTheCryptic]

Thanks so much - I have now had TOO MUCH cake :)

[@kevinmartin7760]

Things go faster if you make some observations from the start. In particular, the cages with small totals are pretty restricted due to the need to contain a digit equal to the cage size: Total 1 made up of just a 1 (but impossible due to other rules, see below) Total 2 is impossible Total 3: 1/2 Total 4 is impossible Total 5: 2/3 Total 6: 2/4 or 1/2/3 Total 7: 2/5 Total 8: 2/6 or 1/3/4 Total 9: 2/7 or 1/3/5 or 2/3/4 Total 10: 2/8 or 3/1/6 or 3/2/5 or 1/2/3/4 Total 11: 2/9 or 3/1/7 or 3/2/6 (highest total for 2-cell cages) Beyond that the possibilities increase fast. A 2-call cage can total between 2 (1/2) and 11 (2/9) but not 4. A 3-cell cage can total between 6 (1/2/3) and 20 (3/8/9) but not 7. In general an n-cell cage cannot total to one more than the triangular number for n. A 1-cell cage (total 1) would have a Kropke dot on it, which perforce would connect it to a cage of total 2, which is impossible, so 1-cell cages are impossible as well. Finally, the negative constraint on dots means that any isolated edge that contains a dot must have at each end at least one cage boundary at right angle to it. If this were not the case, there would be a straight continuation of the cage boundary, and it would separate the same two cages, and so would have to have the same Kropke dot on it. Actually I think there is even a stronger statement: That each end of a segment with a Kropke dot on it must be branched; if the cage boundary only continues in one direction it will separate the same cages and a dot would be needed.

[@christophstahl8169]

Happy Birthday Simon. What a present this was, wonderful wonderful puzzle that never felt too difficult but took so long to solve. How everything fits together and falls into place is a joy to experience. I found myself getting ahead with sudoku staring at a deadly pattern at the end and only then I finished creating the cages and they of course resolved everything. Exactly like Simon. I am still amazed at that puzzle. That was truly special.

[@crhodgkin]

Happy Birthday, Simon and thank you for all you do! I hope you get lots of cake (or pie). :)

[@CrackingTheCryptic]

Hi Cameron, I did! Picture here: twitter.com/crypticcracking/status/1534574737971625984 And thank you so much for the donation!

[@Chris-pm9uw]

Happy Birthday Simon! I'm watching your videos for almost a year now and I never tried to solve them myself. I got the Killer-Sudoku app though and have more than half the puzzles solved. Today I tried this puzzle and wanted to know how far I can go. I actually finished with exactly 2 hours on the clock! I'm very proud of me and you should be proud of yourself too, because without your videos I probably would still look at an empty grid. Thank you for the entertainment and wisdom you provide to all of us. Greetings Chris PS: I hope you got a lot of cake ;)

[@kyaniteice]

Can I just say, this was my favourite video of the year so far - if only because of the mission impossible theme running through my head as you're running out of time! Happy Birthday Simon, this was a fantastic solve and I loved it!!

[@dangrene617]

R3C4 being not blue and therefore R5C5 being blue was available far earlier by something beautiful I was hoping you'd see eventually, but you got there by avoiding the repeated 7. Notice that box 1's green cage is a 20, just like box 2's yellow cage, and since blue was in a white dot relationship with yellow, it would also need a white dot if it abutted green. Beautiful negative constraint situation due to two different cages with the same total!

[@johnh2052]

Yep. That was available from the time the blue cage was being investigated. I think it was there on purpose. (That said, I admit I didn't see the first case like this involving the 10 cages for the longest time.)

[@HershoGoldstein]

Happy Birthday Simon. You inspire me every day. Hope you had all the cake you could!!

[@jukmifggugghposer]

This puzzle was great. I’m glad I got to watch Simon solving this, because I’m a long ways away from solving this myself. That last 5 7 pair was a really funny way to end the puzzle.

[@plutollla]

Happy birthday, Simon. I'm just Sudoku engoyer. Each of your videos is good news for me, an opportunity to spend an hour or more in a pleasant atmosphere of misunderstanding or vice versa, to notice something very small (at my level). Thank you for your videos, they also help me learn English :3

[@Cpchurch87]

After shouting at the screen for ages about the 24 in box 5 having a resolution I gave up and instead decided to wish Simon a happy birthday! Thanks for all the great solves

[@Raven-Creations]

This is now one of my favourite puzzles you've ever featured. It's so beautifully set, with lots of interesting, and often very cute logic. It has a nice solution path (if you spot it), and being left with a deadly pattern that is resolved by the final dot was the icing on the cake. As you said, the negative constraint was never used better. Nigel Tufnell would approve of this one - it goes to eleven. I've no real criticisms today, just observations. In your considerations about red in C1, you did your usual trick of getting there the hard way. Your red in box 3 has four cells, but they can't contain a 4, so it must grow. However, it can't be bigger than five, because 6 cells is at least 21, and it has to be 15 or 17. Therefore it's 5 cells, and because R2C8 is at least 6, it must be 17 and be 12356. It can't take the 7 below, so must turn left forming a W pentomino. The cells must be 6, 1, 2, and a 35 pair reading from the top. The blue above it must be at least 3 cells, but cannot get a 3 in its box, and it cannot take all of the cells in its box either, so it must escape via R4C5, pinning the yellow in R4 to two cells, with a maximum sum of 11. This makes the purple in box 4 at most 12. You correctly deduced that red in C1 is missing 14, 23, or 5, but that means it needs a 7, and the only way to get to one is if it's eight cells. So it's missing a 5 (resolving the 56 pair in box 1), it needs a 2, and the only one it can get is R8C2, and R9C1 must be 5, with the 7 in either R8C3 or R9C2. You claimed at one point that your blue in box 7 didn't have to grow, but it can't include a 2, so has to grow, and it can't be 3 cells either, because it can't reach a 3 with its next cell. If it's 4 cells, it can't be 10, because to pick up its 3 it would have to extend straight across to R7C5, but then it can't include a 2. This means its minimum value is 12, so purple in box 4 is at least 11 and cannot include 1, making its minimum 12, but 12 is also its maximum. So purple is 12, yellow is 11, and blue must be 13. This gives so much information, that the puzzle solves itself from here. This does rely mostly on sudoku, which is why you didn't solve it before you had to leave. I got all of the cells filled in by sudoku, except for the 57 deadly pattern, before I even considered any more cages. To resolve the last cage, I started from the 8 in C9, and worked out how far it would have to extend to get to 40. This took me up to the 9 in R8. I did the same starting from the 8 in R8 (the one in R9 would have been just as good), intending to find the overlapping cells, but this couldn't work without hitting two 1s, and starting from the 1 in R8 was just as bad. I enjoyed this so much, I was a bit sorry to complete it. Please Zetamath, make another!

[@Swisswavey]

That was nice, it took me exactly 1 hour which seems pretty respectable. Very good puzzle Zetamath, thank you

[@longwaytotipperary]

This was wonderful! Happy Birthday, Simon! Great puzzle setting Zetamath!

[@psvjw]

Happy birthday Simon. Great puzzle from Zetamath. The way to discover R3C4 wasn't in the blue cage was to realise that the blue cage was summing to either 19 or 21. If R3C4 was blue, it would connect to the 20 cage in box 1 and had to have a white dot.

[@Coyotek4]

1:02:56 ... yeah, this made my 'personal choice' folder of super-special sudokus. Simply astounding!

[@Tesseren]

The most purely enjoyable puzzle I've done in months, maybe the most enjoyable puzzle I've ever done. An absolute triumph from zetamath.

[@zetamathdoespuzzles]

Thank you!

[@cloudshaveiteasy]

Happy birthday, Simon! May you be surrounded by all your loved ones and lots and lots of cake! Much love

[@a09nton]

Wow! I really love such puzzles! Not monstrously hard, possible for solving by simple human! 1.5 hours of mind pleasure for me! Happy birthday, Simon!

[@siyuanhuo7301]

Alternate method for 1:26:48. The 135 triple in box 5 places 6 in r6c4, 4 in r6c5, and 2 in r5c6. This makes the 22 cage we need to have a total of a confirmed 18 (4+6+8). The cage cannot be a size 4 because it would need a second 4, so it must be a size 5. That confirmed 18 total also means r5c4 must be a 1, as a 5 makes the cage total a 23, but this now leads to a contradiction. We already have 19, so normally the last digit would need to be a 3, but that would mean that there's no 5 in a cage of size 5, breaking the rules of the puzzle. Thus, 8 cannot be in the 22 cage.

[@Infantry12345]

I like watching all the puzzles done on this channel, but this was something truly special. So baffling at the start, but some very interesting quirks helping to solve the rest of it. A very good choice for your birthday :)

[@chrisbattey]

Happy birthday! That puzzle was a joy. So much to play with! I got the 19 cage placed more quickly because I noticed that if it extended to the left it would touch another 20 cage, but I completely missed the fact that the left-side 40 cage couldn't be a 10 cage because it was adjacent to a 9 cage, and didn't resolve that until I'd ruled 3 out from column 1 in box 4.

[@ericpraline1302]

Beautiful stuff from zetamath as usual. I always find his puzzles challenging, but at the same time the logic always flows like golden syrup. It's not often my solve time is considerably shorter than Simon's video length.

[@humanbirdsong]

Gorgeous puzzle, wonderful solve - thank you Simon and Zetamath!

[@amysteele2488]

Happy Birthday Simon! Hope you had lots of cake!

[@maurobraunstein9497]

This was an extremely hard puzzle and I'm very proud of having solved it. It took me pretty much all day on and off, but I still did it! Thanks for showcasing puzzles like these!

[@dannstarrjp]

1:27:16 I love how complicated Simon makes things look sometimes, 2 is literally a naked single in box 5 which was available from 15min before, and not only that, there’s also been a 135 triple there for almost 10 minutes which would just resolve everything easily😉

[@wolframiaa]

Happy birthday Simon!! Hope you had lots of cake 🎂

[@LiquorStoreJon]

HAPPY BIRTHDAY, SIMON!!

[@johnh2052]

At 1:20:00, Simon pencils 13 into R5C5. He notices the 135 triple in row 5, which is helpful, but doesn't notice the 135 triple in box 5, which was critical. And I don't understand it because I was _willing_ him to see it with all the mind power I had!

[@Adrian_Grey]

Happy Birthday Simon!!! I hope you have lots and lots of cake!

[@fornife5004]

A great rule set is a foundation for a brilliant puzzle. Bravo.

[@andrewnelson2525]

I personally found this puzzle quite amusing when I could suddenly fill out the entire grid except for a single deadly pattern of four cells, then saw that it was going to take three clues and a lot of logic to resolve that simple conundrum! Two hours for me, which considering a video of over an hour and a half is more than satisfying.

[@Donrafa189]

Happy birthday Simon. Finding you and mark and your channel has been a great present for me (and I have been able to share your minds with my 6 year old daughter, Aurora, who loves the livestreams you do. She calls them b’benture [adventure] puzzles” So happy birthday to you!! And thank you!

[@spooony2714]

Fabulous puzzle and a fabulous solve. Happy Birthday Simon!

[@ClintWebb]

I spent a long time trying to figure this out, and eventually came to the conclusion that it was impossible, so I then started watching Simon's video to find the little trick I just couldnt find.... only to discover that I had missunderstood the rules, and thought that the gray shaded square (r9c5) was the _only_ cell that wasn't in part of any cage, and then I had stupidly thought that there was a negative restraint on it. Once I had locked in r2c3, I assumed it was a 1 (which meant a 1 had to go in r1c4). BAH! Loved watching the solve though, and fantastic puzzle.

[@justinpreston4152]

I totally agree - the rules did not say there were any more grey cells and I thought that this was the only cell not in a cage - the rules were complicated and this could have been made much clearer - when rules get complicated more people give up before even starting

[@CaptainSpock1701]

Happy birthday Simon. It may be your birthday but I think we are the ones getting the presents with all the awesome videos you guys produce. If you would just permit me to say a quick happy birthday to my son as well. He celebrated his 22nd birthday a while ago on the 25th of May but it turned out that would be his last one. He passed away from Covid on Monday. Even through the grief and heartache, you guys still brings a little bit of normality into our world. This is still an awesome corner of the internet and I just wanted to really thank you for that. While we grief, he is dancing with the Lord. Meanwhile life goes on for us but you guys make it just a little easier and I just wanted to thank you for that.

[@Rach881101]

Happy birthday Simon (and Qodex as well). Your channel has renewed my interest in Sudoku and pencil puzzles, and brings a certain calm during the pandemic.

[@AquaMusica305]

Happy birthday Simon!!! I love watching your videos it gives me something to help make me think outside the box and get my mind working Keep being you, you are awesome!!

[@tachyonrailgun]

Happy birthday Simon! I love watching your videos and it got me doing sudoku in my free time. I really appreciate the solves!

[@andersosterholm2538]

Quite possibly the best puzzle I've seen on the channel and a very appropriate birthday present for Simon! 😃 Happy birthday!🥞

[@stevieinselby]

That was fantastic, both the puzzle and the solve 👍🏻👍🏻 I was pleased to realise very quickly that you could never have a 1-cell cage, and that when you draw a cage boundary through a dot then you _must_ have at least a 3-way junction of cage boundaries immediately on each side of it - Simon seemed to take a long time to twig what the pattern was there and seemed to be working it out afresh every time. But then I missed the possibility of the blue 19-cage having a 2-1 in the tail, assumed it had to be 4 cells ending with a 3, and it all went 🍐 shaped...

[@mr.mindor]

Happy Birthday! This was a fantastic puzzle. I feel your time was pretty reasonable. I finished a bit ahead of you this time, but I also turned to sudoku sooner and that allowed some quicker determination some of the mid game cages.

[@aleksandartasevski1576]

Happy birthday Simon! Hope you enjoy your day and have lots of cake! :) And thanks for this puzzle , enjoyed solving it! Absolutely amazing!

[@linkaut]

*looks at video length* Uhhh, we're in for a treat! And happy birthday Simon!

[@JohnHazl]

I love how two of the last three cages first and foremost serve the purpose of making you think they're going to disambiguate the 57 pair... but then don't. Brutal xD

[@Gonzalo_Garcia_]

45:48 for me. Awesome puzzle! I loved the idea, it was so much fun to solve. And a very happy birthday to Simon!!

[@ahmelija]

Happy birthday Simon! Wishing you all the best. Love the videos.

[@keller149]

Happy Birthday Simon - Thanks for all the wonderful solves 🥳

[@Fun_maths]

It's quite entertaining to always see simon say "I have no idea where to start this puzzle" and then follow it up with "well I suppose I can say that..." and then it just snowballs from there

[@Tankorr]

Happy birthday, Simon! Thank you for being such a lovely human being and for introducing me to the joys of Sudoku.

[@laincoubert7236]

what an amazing puzzle! i can't imagine how zetamath set it, there's just so many nuances... happy bday btw!!

[@patrickdematosribeiro1845]

Happy birthday Simon. Great solve At 1:16 there is another way to see r3c4 is not blue using the negative constraint: Blue shares a white dot with the yellow 20-cage. If r3c4 was blue there would have to be a white dot between r3c3 and r3c4, because the green cage is also a 20-cage.

[@waynemv]

Hard but I really enjoyed it. Took me over two hours. Thanks, Zetamath.

[@razkinzmangowurzel]

happy birthday simon love the content keep it up

[@wydadiyoun]

magnificent! one of puzzles I have ever solved! all hail zetamath!

[@anwenroberts7887]

Happy Birthday Simon!! Have lots and lots of cake!

[@peterkelley6344]

Happy Birthday Simon. Hope you had LOTS of Sudoku Cake!

[@abraxasnl]

Working on your birthday… Oh my. Much gratitude though. Happy birthday, Simon! 🎉 I hope you had lots of cake 😁

[@andrewcook8093]

What an amazing puzzle. Looking at it I couldn’t see any way of even starting it. But once you have a few deductions and work out how the negative constraint affects thing it’s amazing the things you can work out that just looked impossible before.

[@stumbling]

Phistomefel has a thermo put aside for me!

[@julianriml4860]

Happy birthday Simon I hope you have lots of fantastic cake! Thank you for all the fantastic content

[@tombenizrilevi4803]

Happy birthday Simon! Thank you for lighting a spark for Sudoku in our hearts!

[@AichoOshiro]

Many happy returns Simon! What a superb puzzle and a superb solve! Your videos have become a daily staple, much better than daily soap operas or binge watching Netflix! Hope you had a splendid day!

[@alarictaqiarentza9451]

Happy birthday Simon! Thank you very much for bringing such amazing content every day! 🎉🎉

[@puritan745]

Wow, that is a beautiful genius level puzzle, thank you Zetamath!!

[@David_K_Booth]

Happy Birthday Simon, I hope and trust that there was extravagant cakage.

[@CrackingTheCryptic]

Hi David, There was indeed cakage - with the correct ratio of icing to cake (ie 1:1) :) Thank you for the donation!

[@planchapain1]

the progression in this puzzle is amazing, very butifull journey.

[@shiverian5970]

Happy birthday Simon! Thanks for brightening my day with with amazing logic and missing basic sudoku :)

[@JalebJay]

1:04:00 an easier way to see contradiction is looking at the green 3+8+9=20 cage. If you had yellow + blue = 19 or 21 then it has to have white dots next to the green cage. But then that breaks the rules in multiple spots.

[@davidhavard335]

Happy birthday Simon! Another beautiful soduku!

[@majesticjedi0445]

Happy Birthday Simon! Hope you had much cake!

[@AlonAltman]

Happy birthday Simon! 🎉🎉

[@wolfien8]

Happy Birthday Simon! Thanks for your continual joy and enthusiasm. On another note, the blue cage in box 3 could never connect to the green cage as the green and yellow cape both were 20 cages. You could have figured out that the blue had to go further down much earlier and it would have forced that yellow and blue were different.

[@piarittersporn]

Happy birthday, Simon. I wish you all the best and as much of your favorite cakes as your stomach can handle. It was a great pleasure watching you solve this gigantic puzzle and reading the empathetic comments in the live chat. Your solution was a true masterpiece. 👍🎂🎂🎂🍰🍰🍰❤🙂

[@erino7960]

This was quite a nice gift for my own birthday the next day.

[@patrickcarrigan7848]

Happy birthday Simon! Thank you for all the joy and wholesomeness you've provided me over the last 2 years. I hope you eat tons of cake.

[@killamoosdraree730]

Happy Birthday! May you enjoy plentiful amounts of your favorite cake!!