The Sudoku I Wish I'd Made

** Today's Sudoku **
Today's puzzle is called Campfire and it's by Nahileon. This is quite simply breath-taking from start to finish. It also uses a ruleset that we think has SO much potential. Do give it a try at the link below:
app.crackingth...
Rules:
Normal sudoku rules apply. For each line, digits on that line have an equal sum within each box the line passes through. Cells separated by a white dot contain consecutive digits. Cells separated by a black dot contain digits in a 1:2 ratio.
** New Patreon Content **
To all our patrons - thank you so much for your support.
Five new items are now available:
- Mark's solve of Phistomefel's new Sequence Sudoku. Simon's solve of the same puzzle will appear on Patreon v soon.
- Simon's solve of Fillomino Aquarium - the new beast of a puzzle by Phistomefel.
- Mark's latest solve of The Times Club Monthly Special crossword.
- the complete suite of solution videos (all 45 of them!!) to the Pyramid Puzzle Hunt.
- January's monthly reward: A Star Wars themed sudoku hunt by Peter C Hayward.
Coming Soon: The QAS ("Quite Approachable Sudoku") Hunt! 1 Februrary :)
You can join us on Patreon for as little as $2/month here:
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[@suttonstrother7035]

No matter how many times Simon says "The secret is something I only tell my favorite people," it always makes me smile like I'm in on something.

[@lucyg00se]

every single time

[@Rebecca-bk9bd]

I just wanted to thank you for this series and channel. I’ve always had a lot of struggle with maths and logical stuff due to mental issues. I’ve always felt stupid so I never really cared about this sort of stuff, but watching you explain every thought process helps me understand that I am smart, I can understand this stuff, I just need a bit of extra help in a different way. Thank you, this series means so much to me ❤️

[@EelcoWind]

I just spent the entire evening sitting at a campfire with friends, but went inside because it got too cold. Turned on computer, went to CtC... MORE CAMPFIRE! Woohoo!

[@tabularasa0606]

And more friends!

[@AlexKuz]

@@tabularasa0606 idk why but your comment just made me feel so warm for this community... I'm happy I'm here

[@CauchyIntegralFormula]

45'35". What a beautiful puzzle. I especially appreciate how nearly symmetric the clues are, and yet one difference gives the puzzle a unique solution

[@erinmcgee1160]

Anybody else get a warm fuzzy feeling when Simon says "I only tell the secret to my favorite people" and then tells you the secret or am I just weird

[@solfeinberg437]

You're just weird. ;)

[@lorenzocasati2881]

Me too!

[@inspiringsand123]

Rules: 04:31 Let's Get Cracking: 06:21 Puzzle Solved: 45:57 Simon's time: 39m36s What about this video's Top Tier Simarkisms?! Phistomefel: 2x (03:47, 04:00) Bobbins: 1x (21:21) And how about this video's Simarkisms?! Beautiful: 13x (05:36, 11:11, 17:24, 23:36, 25:33, 28:28, 32:08, 34:34, 34:36, 36:14, 36:14, 40:12, 43:41) Hang On: 8x (10:29, 19:40, 19:45, 22:46, 23:16, 23:16, 36:20, 42:10) Sorry: 7x (03:56, 09:10, 14:07, 19:07, 21:21, 36:24, 42:14) In Fact: 6x (13:12, 17:42, 28:50, 29:00, 32:06, 35:21) Secret: 5x (11:07, 11:18, 11:20, 11:20, 11:24) By Sudoku: 5x (34:08, 42:39, 42:55, 42:57, 43:16) Clever: 4x (00:36, 05:00, 20:03, 22:29) Incredible: 2x (00:26, 02:03) Ridiculous: 2x (25:19, 25:21) Magnificent: 2x (03:25, 45:57) Wow: 2x (46:28, 46:28) Good Grief: 1x (45:29) What on Earth: 1x (38:01) Useless: 1x (37:52) Goodness: 1x (33:57) Nonsense: 1x (40:40) Lovely: 1x (42:04) Brilliant: 1x (41:46) Gorgeous: 1x (46:26) Take a Bow: 1x (46:06) Shouting: 1x (42:12) Approachable: 1x (02:44) Of All Things: 1x (39:22) Stunning: 1x (26:08) Corollary: 1x (20:14) Obviously: 1x (03:14) Progress: 1x (35:29) Most popular number(>9), digit and colour this video: Fifteen (13 mentions) Two, Six (75 mentions) Blue (32 mentions) Antithesis Battles: High (22) - Low (8) Even (7) - Odd (1) 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!

[@roughryder5]

You need to get out more

[@Jonimasters1997]

@@roughryder5 you know what a bot is? It is not a human typing this under each video man 😅

[@smylesg]

27:41 How about "flurry of digits"? Also, using colors as verbs: "blued", "oranging", etc.

[@mumiemonstret]

26:30 That's our first digit (I think this phrase could qualify in the progress list at the top. It is uttered quite often.)

[@Yahula1edits]

The funny thing is, as a german i didnt find this channel via LogicMasters Germany, but by browsing through videos on how to solve no digit killer sudokus, and thats where i heard for the first time "The secret, i only tell my most beloved people, is every row and column and box consists of the numbers 1-9 and those add to 45..."

[@vikingslayer34]

Phistomephel: Pronoun Phistomephel box: Noun “Are we going to have to Phistomephel here? Verb Phistomephelian: Adjective Man I love this channel!

[@Vallam23]

you mean "proper noun", not pronoun?

[@vikingslayer34]

@@Vallam23 Yeah probably. I didn’t pay much attention in English class.

[@wizardjokes]

Phistomephel is the other gender

[@garrettsmith9788]

Thank you for fixing the orange 1. Order in the universe has been restored.

[@P_44_44]

I love when Simon tells about a secret :) It makes me smile every single time

[@francescopetracca374]

Smooth solve from the beginning to the end. This demonstrates the excellent construction of this puzzle. Good work to both of you!

[@joelstevens5670]

The logic in that sudoku was so good it was just ridiculous! Among my favourite deductions were the black kropki disambiguating the pairs adding to 15, the effect of the white kropki in column 5 on box 5 and the bottom ‘equal sum’ line having a 7 and a 9 on it. Many thanks to Nahileon for an absolutely magnificent piece of puzzle setting and also to Simon for a rather beautiful solve. That was quite incredible. :)

[@Kingcob7]

This is one of the few puzzles I have opened, looked at for 10 seconds, and immediately decided to leave it for Simon to solve for me.

[@G.Aaron.Fisher]

23:18 This was my favorite deduction of the puzzle. It definitely felt novel, despite its simplicity.

[@th.nd.r]

WHAT AN INCREDIBLE PUZZLE. WOW. LOVED THAT. The setting is magnificent, the solving is magnificent. So many moments of joy I can’t count them. Nahileon and Simon, take a bow. Incredible. EDIT: I also wanted to thank Simon for introducing me to the word “genuflecting”!

[@jasond4084]

Does it matter to KZbin and it’s algorithm (for your channel) if I watch these at 2x speed? I’m not quite as locked down as I used to be but can’t not watch every single solve. My sudoku game gets elevated every day! I’ve gone into the archives and solved some of your old work that I could not have touched a year ago. Thank you Simon and Mark!

[@kimberlypreston6204]

I am solving older ones I wouldn't have been able to do last year either. :)

[@MihirRai398]

Watching a video at 2x speed will make the video end 2x faster, which will reduce the viewer retention rate, which will affect how the algorithm looks at that video.

[@KinkyTurtle]

I watch them at 2x speed too, which has the added benefit of making Simon & Mark sound even smarter than they really are.

[@jasond4084]

@@MihirRai398 but it does allow me to have time to watch both of them and try many. So, sorry Mark and Simon 🤷‍♂️ it’s only the hour plus vids that get the full 2x. Most of them it’s 1.25 or 1.5 so I can follow. I’m slowly making my way through the book too.

[@nathanisbored]

i watch all of these in 2x speed

[@Rubrickety]

Absolutely gorgeous. After the initial break-in and pinning down the 15s, I got stuck for a very long time before realizing the power of the black dots. I loved that the grid held only the tiniest of asymmetries to force uniqueness.

[@dwebb2805]

16:00 simon goes through a lot of trouble to prove a 6789 quadruple in different boxes (and even marks them with a yellow flash) 27:28 simon gets a 78 pair on the right side of the quadruple and doesn't use it to get the 69 pair on the other side :P brilliant solve regardless, happy to have found this channel about a month ago

[@956675]

What a brilliant puzzle. I couldn't do it myself but I very much enjoyed the solve. Very well done Nahileon and Simon.

[@fanyaugusts9760]

Proud of been able to make this puzzle by my self without Simon help. Something unimaginable just a while back, and all thanks to Cracking The Criptic

[@GrantMcLean]

Thanks Nahileon for an absolutely wonderful puzzle, and thanks Simon for the kind of solve the puzzle deserved.

[@willieloeffen9291]

Started this by colouring box 2 and row 7 blue, then boxes 4 and 6 orange (2 sets of 45 each). Then remove the equal sum lines from the coloured boxes/rows and you end up with blues being 12345 (minimum) and oranges being 6789 (maximum). Sort of set theory, but without overlapping colours 😁. From there the colouring of the grid starts. Made it in 57 minutes myself. Not fast, but quite happy with that.

[@gregind01]

What an utterly brilliant puzzle!!! It is approachable by us mere mortals, but the logic is astonishing right from the start to finish! 😁

[@ericpraline1302]

Agree about the equal lines rule. This was a lovely puzzle which I initially mangled before finding a very satisfying way through.

[@AussieJohnny]

What a brilliant puzzle, Nahileon. The break-in wasn't too hard....just maths. But it still took lots of great logic right to the end to solve the puzzle. Now I can have the extra joy of watching Simon's solve and I know he will be spellbound by your construction. Thank you.

[@emilywilliams3237]

"...it's probably one of the most wonderful digits we've ever shown on the channel." Priceless.

[@magnumpolmatier8184]

I’ve started watching your older videos in an attempt to up my sudoku game. For the most part it seems to be working. Your newer games are amazing; and the have certainly made me a better player, but watching your older and less refined videos are certainly helping as well

[@theashen]

Super clever puzzle with a nice ruleset. Very enjoyable solve

[@HalfBakedLunatic]

Stunningly clever puzzle from start to finish!

[@jaega4247]

Great puzzle, and a beautiful solve by Simon as always! Was going well for me all the way to the bottom. Had to get some help from Simon (at 39:21) to get it all done before bed time.

[@jaymuse127]

I like fire. That logic of finding the 15 summed in box 6 was delicious

[@Paolo_De_Leva]

😏👍 Yes, I agree 💯%: beautiful logic *"from start to finish"* A kind of setting that is *"Phistomefelian in its conception and execution,"* meaning that it is a completely new idea, which has been showcased in its most beautiful possible implementation.

[@ahouyearno]

I love how the symmetry is broken with exactly one square

[@longwaytotipperary]

Unwinding with a 🍷and Simon solving. At least for a little while, life makes sense.

[@sampathkumar-ej7xl]

Nahileon - What a fantastic puzzle you came up with. I am yet to watch the route Simon took to solve but I ended up using SET theory for the initial breakins. It was very satisfying. Thanks. Also big thanks to Mark and Simon who have enabled me to solve this kind of puzzle with their fantastic daily solutions. I was one who only wanted the classic sudokus and nothing else.

[@bentaylor4203]

Amazing puzzle, this one was great fun to solve

[@bristolrovers27]

Excellent puzzle

[@Coyotek4]

42:01 ... after having my solving streak snapped yesterday, I'm glad to have gotten back on the 'plus' side with this one. Nice puzzle!

[@AurelUrban]

The logic in this puzzle was so smooooth. Took me a LOT longer than Simon but the solve was very satisfying. I was really surprised by how integral the kropki dots were to the solve. Really makes you appreciate the setting. And the logic of the bottom line was so good!! I was honestly taken aback when I realised all the options eliminate themselves when I consider them properly. But of course the cake goes to the breakthrough, I felt SO smart when I determined all the sums of the top lines :D Obviously the real smart person here is the setter, but it was a good feeling regardless.

[@magnusholmfreysson2828]

Great sudoku; and I also loved your escape simulator, hope to see more of it

[@riluna3695]

Good lord this puzzle. It took me over 25 minutes just to find the initial breakin and get ANYTHING in the grid, but that wasn't even for lack of seeing anything. It was just a heck of a lot to parse and keep track of, and needing to find more and more ways to keep restricting the possibilities until only one was left. The entire rest of the puzzle took less time than it took to get my foot in the door, but don't think for a second that it wasn't fun the entire way through. That was excellent setting. I don't know how these people find these things.

[@crystalgehrt8861]

Clever setting, beautiful solve.

[@hornetgamer8980]

Completely agree about this ruleset. It creates the most approachable form of zero given digit puzzles, while still requiring some nimble logic.

[@JohnRandomness105]

The board looked almost perfectly symmetric, which led me to conclude that a unique solution couldn't exist. But then I noticed one subtle asymmetry.

[@YourFavouriteDraugr]

Absolutely fantastic puzzle, but exaggerated by Simon making it look 3x more difficult than it needed to be. Really does prove that when recording these videos, sudoku skills seemingly magically disappear from whichever one of the to is making it.

[@andrewnelson2525]

"Phistomefelian" is my new favorite word.

[@MetalRufflez]

I can usually follow Simon logic deductions and explanations pretty well (but I’m still terrible at spotting them), but this one flew totally above my head, and I don’t think it’s Simon’s fault.

[@GretgorPooper]

Speaking of puzzles Simon wishes he had made, I'd love to play puzzles set by Simon and Mark themselves.

[@PathOfShrines]

Wow, cool new rule, very promising! 52:44; I got the 30 constraint pretty quickly, but it took me awhile to figure out the 15 restriction and then realize that coloring was going to be useful.

[@shteevuk]

This might be my new favorite puzzle! It's just so astonishing that *anything* can be deduced at from the start. Grats to Nahileon for this incredible design

[@Raven-Creations]

Another stunningly good puzzle. The intricacy of the interactions was sublime. My break-in used SET, with rows 2 & 3 in one set, and boxes 4 & 6 in the other. Removing all lines left me with the same situation that you found. Studying the only break in the symmetry pointed me to the logic with the fifteen segments. Really fun to solve, my colouring was a bit more thorough at the start, so I new there had to be a high on both black dots, and because of the highs in R7, they had to be different. Other than that, my solve was pretty much the same. The logic forcing fifteens onto the line segments in boxes 3 to 9 was lovely, as was the 9s at the end. There was a lovely flow to this, which is always nice, and it didn't give up its secrets in one go.

[@cjbailey3646]

Usually I'm content to watch and wonder when Simon's going to find deductions I notice before him, but this time after he got the break-in I saw an opportunity to take a different approach, so I solved it myself. Instead of going with high-low coloring, I gave the high digits their own colors - I think it got me to the realization that the sum for the outside lines was 15 a little quicker, but for everything that followed I think it was a bit confusing. I eventually started thinking in terms of high pairs of 15, less than 15, or more than 15 - and I'm not sure how useful that was either, as opposed to thinking purely in terms of high/low digits. But I solved it, so I'm happy enough with myself.

[@laurenseale9683]

For the escape simulator game, there are some sudoku custom levels! I was actually able to figure one out, so I’m sure it’s part of the game you would make short work of!

[@aristotelismetaxas7802]

I was staring at the 5 blues in c5 for quite some time and thinking "you have got to be kidding me Simon..."

[@dontmindme2844]

How does someone setup a puzzle like this? It's amazing the way the logic bounces around and forces a unique result across sections...

[@msolec2000]

The four oranges in column 5 were available from the beginning, but other than that, nice solve.

[@nilsp9426]

41:57 "W pentomino of blueage in box 9" nerdiness level of fun fact over 9000

[@worknlurk5931]

At 18:35 Simon identifies the 5 low digits in box 6. Given that we already know the domino at C6R2-R3 is high you can postulate that the maximum the 4 digits on the line can add up to is (5+4+3+2) 14, so the domino is

[@Swisswavey]

It's uncanny, I had a puzzle the other day I solved in 44:44 and this one was exactly the same time. I wonder whether Sven's app is trying to tell me something. I've no idea what though! Lovely puzzle, so elegantly put together and not impossibly hard either. Wonderful.

[@myrddin4242]

Reminds me of the Star Trek: Next Generation episode "Cause and Effect". The crew are unknowingly caught in a time loop, with the 'past' iterations of the loop bleeding through to the 'present' as a sub-conscious deja-vu feeling. It's resolved when they use the bleed-thru to encode a message that Data picks up, causing him to notice the number '3' an inordinate number of times, which gives them the clue they need to break the loop. So, the software keeps sending you '4's... could you be stuck in a time loop? Have I asked you that before?

[@victoriam6569]

Not too hard but elegant! Nice puzzle. Thank you!

[@federicocucc7852]

Ah this one is great! Highly recommended!

[@Sam_weiqi]

Genuflecting. Nice word. Didn't expect to be learning English here, but there you go :)

[@bradleyemery]

Me, behind my screen: "SIMONNNNNNNNNNNNN" Simon: "Oh, I've made that the wrong color, people are probably shouting at me"

[@AndreAy1975]

Solved it with lots of help from the video.

[@mikepictor]

I kept thinking "It's mad that this has a unique solution" and it kept solving.

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

25:15 for me. loved it,

[@paul-juniorblack6151]

One thing I love about these puzzles is I have no clue to start them and by midway in the puzzle when Simon has done all the hard bits I'm like "wait logic there means that look at it again". Like 21:45 onward. It can't be 6,7,1,2 because that would mean 3 low digits. Max you can make it is 5,4,3 which is 12. But the minimum above is 6,7 which is 13. So no its one low and 2 high but he didn't see that at the time

[@shalaz1981]

Simon stanning out on a new setter is only going to aggravate Phistomefel. Don’t do it!

[@minamagdy4126]

Yeah, he might set another puzzle for Mark to solve first

[@ApesAmongUs]

The 134 was sitting in column 8 with a 3 and 4 looking at it for so long, and he solved it without ever paying attention to what was already in column 8.

[@thomasfrewer1328]

The fact that this can still be solved even though it's almost entirely symmetric is very cool.

[@Tsevion.7]

I did the breakin a bit differently using Set. Compared Box 4 + Box 6 vs. Box 2 and Row 7. After cancelling out with the lines it leaves you a T in Box 2 and 5 cells in row 7 vs. just 4 cells in row 6. Two sets of five is minimum 30 and one set of 4 is maximum 30, and the high/low coloring fills itself in. Pretty much the same solve path as Simon after that though, finished it in 42 minutes.

[@the2fang2gang]

Amazing solve!! My only complaint: Simon, PLEASE take away the color flashes when they are no longer doing anything, or at the very least once the puzzle is complete. I love looking at the clean finished grid, must be me OCD :D

[@S_Black]

You seem to have forgotten that the yellow cells were a quadruple. So the ones in box 1 had to be 69 all after the 78 in box 3 was established

[@kimberlypreston6204]

Great puzzle!

[@jumpierwolf]

I love the phistomefelian term.

[@itioticginger9520]

17:20 looks at column 9 for having 4 blue digits already so there must be 4 orange and 1 remaining blue, but entirely ignores that column 5 has all 5 blue digits already! xD

[@willemm9356]

39:30 Classic Simonism... :) 3 of the high digits in box 7 are used up as well, which directly leads to the resolution of the 9 x-wing.

[@emo6577]

Since you were talking about upcoming sudoku competitions I’ve been wondering for a while - how do setters control the difficulty of a puzzle if they’re commissioned for something like a major competition? Because I know they must be novel puzzles/made for a comp to make sure no solver has seen it before. Just curious, the thought has been in the back of my brain for a bit!

[@ohno-wi1vb]

Interesting question I’d like to know as well. I assume there are testers but they have to keep secret

[@mceajc]

Wonderful!

[@Zach_Bliss]

You guys should react to the Sudoku championship

[@AvatarBowler]

Bit of a meager deduction, but the answer to “Is it exactly 1 high digit?” at 21:04 is already yes at this point. If there were 2 high/orange digits in that group of 4 cells, then the other 3 cells in box 4 would be blue and have a maximum value of 12 (3+4+5), which is impossible because the minimum value of an equal line is 13 (6+7). Don’t do that, you’ll get the puzzle wrong. 😁

[@HunterJE]

It gave me a bit of an itch at the base of my skull having four blue cells in column 5 and the rest of them not oranged in

[@mijnvaderisdepaus]

The picture in the beginning says that Sudokupad is coming soon to windows. But it's on steam already!

[@samueldeandrade8535]

41:36 digit 1 gets the status of high digit! Hahaha

[@boahnation9932]

Incredible

[@Ciiran]

The biggest question I have is: what is the frenetic clattering on the keyboard when Simon is going for a digit or a pencil mark? Why the racket? Am I missing keyboard commands when I'm solving myself?

[@joshleroux6731]

I was halfway through my comment about the orange 1 when you caught it

[@Gonzalo_Garcia_]

27:15 for me. Nice puzzle!!

[@TabAtkinsJr]

41:45 :watches Simon color a 1 orange: SIMON NOOOOO

[@TabAtkinsJr]

42:15 PHEW

[@stephenmccarthy1795]

Note when there are five blues in column 5.

[@LednacekZ]

37:48 for me. Even though i got a bit lost at the end.

[@cdigames]

I hate to admit that I nearly had this one in around 50 minutes, but misplaced one number and spent thirty minutes figuring out what I had done wrong.

[@israelRaizer]

It would be great if Simon used the software in dark mode for these videos, it's easier on the eyes...

[@smylesg]

39:22 That places the 7 in box 9 of all things. Oh, Simon, you're just so silly sometimes.

[@josephrion3514]

28 minutes in the two marked sevens in column one should be resolved because those two digits should be the other pair of fifteen same as the right so a six nine with Seven in the top corner. 33 minutes in you can't have the 9 in column three on the white dot no way to place an eight under the 89 pair in column four. Also it's an 852 pair for fifteen in box four.

[@Nevir202]

Is there a concise term for the "digits on a line..." rule in this puzzle?

[@samrappl9011]

I've been playing along with puzzles on your channel for a while now, and it's been fun, but I have to admit this one was not fun for me. I thought that cells must be separated by a white dot if they were consecutive and must have a black dot if they had a 1:2 ratio, which made the puzzle unsolvable for me and a large waste of time. :(. The math was still fun, but the puzzle was a huge disappointment. Was I the only one who thought this, or did anyone else have this issue with rules clarity this time?

[@tsgsjeremy]

First solve where my reasoning was nearly identical to Simons. (I apologize for the insult. 😂)

[@dobraf]

19:27 if you had put in the options (123456) into r4c6, you would have been able to remove the 6 from those options and colored the cell blue at 20:14 when you deduced that 6 had to be in one of the two cells above it. As it stands, you didn't get that deduction until 29:43. Maybe it's time to stop making fun of "Pencil Mark"? :D

[@johnedwards7473]

The moment he put the 6 corner marks in I thought “and now Mark would know R4C6 is blue.”

[@BlossomBlue3479]

It's so Simon to put in place a yellow colouring and then ignore it and find some other way to get to the same point.