Fun with a Bizarre New Sudoku Rule

Added: 2026-05-13

[00:00:14]Hello. Welcome back to Cracking the Cryptic. And uh on screen, a puzzle featuring a new type of cage, the Tesbus cage. And it's by a new setter. And actually, their name I think means newish. I don't know. There might be other meanings to neon, but lots of new there. And uh what's new to Patreon?

[00:00:35]There's um Simon Solve of Oscar's crossword there. If you like the crossword videos, that's on Patreon. Um along with the Spider-Man Sudoku hunt for the month along with Grid and Connections videos. Lots going on. Do check it out. Patreon's good fun. And there are apps. We have Killer Sodoku as an app. I don't think today is really about killer cages. TZBus cages seem to be different, but uh nonetheless, we have a lot of apps and they include classic Sedoku 2 and the worms by the likes of our friend Blobs. Do check out the eclectic sedoku worm. It's good fun.

[00:01:14]Uh they've also got a bit of merch. If you want to Marty Sears Ratr run merch or something like that, check out again the links under the video. They always have this stuff, but they also have a link to this puzzle. It's called busy busway by Neesk. And uh yes, there are definite reversals in it. So, let me explain the rules. Normal Sedoka rules apply 1 to nine in every row, column, and 3x3 box. There's not many more rules. A cage cannot include every digit from another cage.

[00:01:47]That's the rule. In other words, no cage is a subset of any other. the digits in a cage do not appear in in another cage.

[00:01:58]Uh that's it. That's all we need to solve this puzzle. I mean it's a fascinating idea. Um do give it a try on the first link. I I Yeah, I don't know.

[00:02:09]I think it might be difficult. Let's get cracking.

[00:02:14]Um okay, there's Sudoku. I can stick a three in box one thanks to the position of these threes. Nearly a six in box nine, but not quite. That's going to give me a six in one of those cells.

[00:02:28]Ooh, it's going to give me a six in one of these. Now, that might be as much as I can do in Sudoku terms straight off the bat.

[00:02:38]Doesn't look like there's a lot elsewhere. I mean, we've got a few given digits, but not many.

[00:02:46]But let's think about the cages.

[00:02:48]So, let's think about the one cell cages. For some reason, I thought there were three one cell cages, but now I believe there are two.

[00:02:58]Um, right. Whatever's in this cage, let's make it red.

[00:03:05]That digit cannot go in any other cage because that would break the rule.

[00:03:09]Tesbus, by the way, is subset backwards, just in case you hadn't noticed that.

[00:03:13]Anyway, um that would break the TESBA bus cage rule that a cage cannot include every digit from another cage. So it wouldn't be this cage that would break the rule if this red appeared for instance in here. It would be this cage breaking the rule because it would have every digit from this cage. So once this is red and who knows what red is it red can't be in any other cage in the whole puzzle. So none of these cells can be read. So that is a bit of a constraint.

[00:03:47]I'm going to make this cage yellow.

[00:03:49]Obviously, it's not the same. That would break the rules. So that's different.

[00:03:52]Actually, this cage Oh, we've got Oh, we've got three in one of these cells.

[00:03:56]Right. This cage is by Sudoku. It sees 1 2 6 and nine. So this is 3 4 5 7 or eight.

[00:04:08]Now that might be interesting.

[00:04:10]Yellow must not appear in any other cage in the puzzle.

[00:04:18]So let's just think about what this can be.

[00:04:27]I don't know. Is it maybe there's no actual action from that?

[00:04:37]No, no, no, no, no. There is something yellow is in one of these two cells in box six because right that's really good. Yes, yellow must be in one of those two cells because by sudoku it's not in those cells in box six. It's not allowed in another cage. So it must be in one of those two cells. And here it can't be three, seven or eight.

[00:05:00]Well, okay. Here it could be seven, but here it could be four or five.

[00:05:08]because it's got to be the same as the No, hang on. Hang on. I can't put those in that cell. What I can say is yellow cannot be three because it couldn't go in either of those cells and it cannot be eight for the same reason. Now, three in row two is definitely in this cage.

[00:05:27]So, whatever it goes with three and that digit cannot appear in another cage. And now we know yellow is four, five or seven. So, let's think a little bit about that in case we can do anything with it.

[00:05:47]Well, oh god, I'm sorry. I'm going to have to just pause for a second and deal with something. Right. I'm sorry about that.

[00:05:58]Um, wow. This yellow is is yellow and it's not the same as red. Is that interesting?

[00:06:09]No.

[00:06:11]Right. What can red be?

[00:06:14]Yeah. Let's just just ponder that. Red by Sudoku could be 1, two, four, five, six, or seven.

[00:06:24]Um, where's red going in this cage? not into those cells. So into one of these.

[00:06:32]I don't think that instantly rules out any digit.

[00:06:38]I was going to think about where yellow.

[00:06:44]Yeah, hang on. There there there is an interesting point about yellow. Where does yellow go in this row? Because every cell is in a cage apart from this one which can't be yellow by Sudoku.

[00:06:56]and this one which is therefore yellow.

[00:06:59]Well, that's quite interesting. Now, now red can't go in yellow because they can't be the same digit in this box and it can't go there and it can't go in a cage. It must go in one of these two.

[00:07:12]So, it's not two or seven. Well, I mean, I know it's a micro conclusion, but it's something. Red could easily be there in which case red is four and would have to go here. But otherwise it goes here and is one five or six and yellow's up here. What's yellow doing?

[00:07:36]Not really. That was interesting about middle row. Yeah. Where does red go in the middle row? Why don't I just do this simply? Red obviously goes here because it mustn't go in a cage.

[00:07:49]Right. Well, that means we can rule out six from red.

[00:07:54]It is now 1, four or five. Yellow is four, five or seven. Oh, we've just learned it's not four. It's five or seven. Good.

[00:08:04]And red is 1, four or five.

[00:08:09]Now, red is definitely in one of these two cells, and it mustn't be in a cage here. So, it's in one of those two.

[00:08:16]Well, that's just sodoku.

[00:08:18]Yellow.

[00:08:21]Yellow could also be there with red.

[00:08:26]Otherwise, it's in one of these two.

[00:08:29]Yellow is five or seven.

[00:08:33]There's a six in this cage.

[00:08:45]Interesting. But no cigar.

[00:08:56]Yeah, that middle row is very interesting. A lot of caged cells in it.

[00:08:59]What about the middle column? There's some caged cells in that.

[00:09:07]Well, we now know, okay, I'm thinking about red and yellow and where they are allowed to go in the middle column because they're not allowed in the cage cells.

[00:09:18]Red clearly can't be there either because of its various positions in the central rows. Is that any use?

[00:09:32]Is there another aspect to this problem of of of where things go? The middle box has this five cell cage. I I do recognize that boxes four and six have five cells, but this is interesting because everything Yeah, let's let's call that light blue and dark blue. Let's call this violet and per and pink.

[00:10:05]Yeah, this is good. Where do dark blue and light blue go in this box?

[00:10:15]Because they can't both go in the cage or else we would be breaking the TESB bus rule. This cage would have all the digits from that in it. So this can't contain both dark blue and light blue.

[00:10:29]So at least one of them, one of those two colors is outside the cage in box five in one of these cells. The same is clearly true for this. At least one of them is outside. Oh well, this pair has to be one from dark blue and light blue and one from pink and violet and so not red.

[00:10:51]Yes.

[00:10:53]So these include one from dark blue and light blue and one from pink and violet.

[00:10:58]And this is where yellow has to go because it's not allowed in a cage. And now every other color I mean I've invented six colors for the purposes of this puzzle so far.

[00:11:12]The other three and one of those and one of those are populating this Z pentomino cage.

[00:11:21]And therefore, amongst those five colors that I'm now talking about, the three colors I haven't even coined yet, and whatever this is that's not in one of those, and whatever this is that's not in one of those, we can't repeat elsewhere.

[00:11:36]Now, I have a feeling that's going to carry into action in boxes four and six.

[00:11:46]And that is interesting. We and we've got yellow and red much more placed now.

[00:11:52]Oh, look. If yellow was seven, it definitely goes here and here and here.

[00:11:57]Oh, this yellow is not seven. That's yellow. It's looking at this cell. This has become yellow. It's not seven.

[00:12:04]Yellow is five. I've got a digit in the puzzle after 13 and a half minutes. I'm quite pleased with that. That means red is not five, by the way. Red is one or four.

[00:12:15]And it's either one here or four there.

[00:12:19]So either that's red or that's red in columns two and three.

[00:12:27]Interesting. Quite interesting. Maybe not very interesting, but a bit.

[00:12:34]Yeah. So now I should be thinking, okay, this I don't know.

[00:12:41]I was going to say this digit. Let I don't know what which one of these four colors it is, but I do know that it can't go in those cells.

[00:12:50]Oh, I don't know that it can't be six.

[00:12:54]I was going to say it's in one of those three, but it could be a six.

[00:13:05]I'm quite tempted to just label these three digits with colors.

[00:13:17]Well, I mean, what are what are my three remaining colors on my particular palette? They're gray, green, and orange. That's what I have remaining.

[00:13:25]And this cage is going to contain green, gray, and orange. Okay, so that's telling me that green, gray, green, orange, gray, orange, and indeed gray, green, orange can never make up a full cage somewhere else.

[00:13:45]Now, how do I use that?

[00:13:48]And that is a challenge to you cuz I don't know. I feel like these boxes four and six hold a lot of Oh, by the way, this digit now sees all sorts of sodoku.

[00:14:00]It is 2, six, or seven.

[00:14:04]I mean, I know nothing about its color.

[00:14:07]This one is 1 3 4 5 or six. Oh, maybe I I got more information about yellow, didn't I? Yellow is a five and is in one of these cells. Let's sort of half color that.

[00:14:24]Yellow is not here. It's in one of those three. I don't know. Maybe yellow's in one of those three in box one. I thought maybe keeping it out of cages was going to do something. It feels like it didn't.

[00:14:45]Yes, I may be focusing a bit too much on the numbers and I should be doing coloring exercises, but I don't understand what they are yet.

[00:14:57]Okay, this digit is not going to go into this cage, but I just don't I don't know what color it is. I don't know anything about it.

[00:15:12]Okay. Okay. If red is four, then red's actually in that cell as a four. Then it would have to be in one of these three to avoid a cage over here. Then it would be in one of these two. Let's just think about that. We've got certain reds. That would be four all around the board. Um I don't know. That's not doing anything.

[00:15:39]I'm pleased with what Oh, look. Right.

[00:15:43]This digit sees 652 874. And this one sees all of those except four.

[00:15:51]So 2 and 8 in this box are either both in that cage.

[00:16:02]Oh, what can the is there anything that these can't contain?

[00:16:07]Because if we could say two and eight were in there and one of those digits is, but if we could say this was both of those digits, a 28 cage, then this cage couldn't contain both 2 and 8 and one of them would get forced out. Yeah, this may be the point is we need to find a digit in another cage in this puzzle that isn't red, yellow, or either of these two.

[00:16:37]I mean, I suppose orange and gray have to be in this cage. I I wanted to use that earlier. I didn't really figure out how I could.

[00:16:52]Is three in the cage? Yes, it is. Look, these two see a three and they see a six.

[00:17:01]Both of them see three. Oh, no. Hang on.

[00:17:04]This one doesn't. That one sees both sixes. Right. Let's do it with threes.

[00:17:08]These both see threes. Three is in this cage now. That right. This pair is three and Okay, I'm getting Oh, I don't know. No, I was going to use a Right. I'm going to use a letter because I I can't relate this to the colors particularly.

[00:17:32]This cage contains three and a.

[00:17:37]Now three is in this cage. So A can't be in it. One of these two is now A.

[00:17:48]I mean that's interesting. Can I replicate six is in this cage?

[00:17:54]You see, if I could say the same that this was six and no, if I could say that six was definitely in this cage, then this would be six and B.

[00:18:09]Ah, but that's I've got to be so careful because this could be six and A and that would allow A to continue its life outside a cage in box five.

[00:18:20]Oh my goodness. This is just showing I don't understand what's happening in this puzzle.

[00:18:26]This digit is 1 8 or nine. I mean I it's hard to imagine it's helpful to mark that but you just never know.

[00:18:46]If they were a Oh, right. These do not contain red or yellow.

[00:18:58]This cage here that I'm highlighting in box four doesn't contain red or yellow.

[00:19:03]We know that it also doesn't contain three.

[00:19:15]Okay. What I'm interested in is where the two cells in this cage go in this box because they cannot both go in this pentomino. That's the rule.

[00:19:28]And how do we keep them out of there given that they can't be in these cells by sudoku and they're not there? One of them must go here.

[00:19:38]Well, that's quite interesting. So this digit now I don't think my A strategy was a lot of use. Let's get rid of A. Let's call this digit A. That must be in this cage and in one of these two cells. It's not red. So it's not it's not in this cell.

[00:20:03]Now the other digit in this cage is B.

[00:20:11]B will be in this case. Where will B be in this box?

[00:20:21]It won't be red and it won't be in those cells.

[00:20:28]So if B is a seven and this could be sitting here as a seven, then it could be there. But if not, B is going to be in a different cage from A over here, which is I don't know, maybe it's not powerful, but it's something.

[00:20:47]And maybe I should think about this digit.

[00:20:55]I don't think that's doing as much of a good job as a is this digit which has to Yeah, there isn't a two cell cage pointing at this in the same way as that two cell cage A is in one of these two cells and is either 1 2 7 8 or 9 and it's also here as one of those digits.

[00:21:28]Ah, so by that logic this is not six.

[00:21:33]And I was trying earlier to claim that neither of those were six when I mistakenly read what was looking at. But now we know that six is in this cage because that's not six. In fact, six is in one of those two cells now and one of these two. And that's getting a bit more interesting. But the interesting thing about six definitely being in this cage is the other digit from here and I'm now going to call this cage six and B cannot be in that cage. Now the other digit from here can it be yellow?

[00:22:12]No. Yellow is not allowed in a cage.

[00:22:15]So in fact that can't be a five. The other digit from here is not yellow and it's not red and it doesn't go. So six goes in the cage. B can't go here, here, or here in A because it's definitely is B definitely different from A. Oh, that is a million dollar question suddenly.

[00:22:46]Oh bother. This could be six and a just as this is includes A.

[00:22:55]If A was one or seven that No. No.

[00:23:00]My goodness. No. Okay. Why can't B be A?

[00:23:04]Because there'd be two of them in these columns.

[00:23:09]And the only overlapping digit in 1 2 7 8 9 and 1 2 3 4 6 7 is 1 and 7 and they would replicate a third time in the columns and that's impossible. So B cannot be the same as A. And now B has to go here because it has to get outside the cage that six is going in. That is B. That's what I was looking to prove in a way and I've done it. B now cannot be six or three.

[00:23:41]Well, we know it's not six because this was containing six and B. But three cannot be in this cage. Now that I mean it's it's not a massive advance, but it is something.

[00:23:54]This is six and B. B is 1 2 4 or seven and is sitting here.

[00:24:06]I haven't at all thought about how A and B relate to these cages, but I'm not sure I need. I mean, I don't know. Maybe I need to, right? Oh, bother. I was going to say B is now.

[00:24:21]Yeah, I think B is in this cage.

[00:24:27]B is not six because of that.

[00:24:33]If B was not in this cage in this box, remember B is there, so it's ruled out of those cells.

[00:24:40]If B was in this cage in this box, it would be in one of If it wasn't in that cage, it would be in one of these two cells.

[00:24:53]And I thought it couldn't be because that would replicate B between these two dominoes.

[00:25:02]And it can't be 72 or one which would appear a third time in the columns.

[00:25:06]However, maybe B can be four.

[00:25:13]It would be here and here and here.

[00:25:17]Now then red would be one there.

[00:25:27]Oh, maybe that is possible. This I mean I was working on a conclusion that was going to put um be into this cage and then I thought there was some I could keep six out of that cage if I could do that and that would have been quite helpful. Very very helpful.

[00:25:52]Oh goodness. I nearly got there. Well, maybe it doesn't matter. Maybe it doesn't matter. Let me keep thinking about this. This is really detailed stuff, but I It's very very interesting.

[00:26:11]Ah, I can't get it in my head. If B is not B is not six. This is six and B.

[00:26:17]This cage and B is there. It's one, two, four or seven.

[00:26:25]I think it must be well I'm if it's not in this cage B has to be in one of these two cells and it can't be there because it would be 1 2 or 7 and that would replicate three times in two columns which is impossible.

[00:26:43]So if B is not in this cage, B is four and then red is one at that point and this would be a four.

[00:27:00]Then red is one and this is red and is one and that would force this to be six.

[00:27:11]So in that circumstance we get a six here and a one here and one is red. In the other circumstance where B is not six. No. What am I talking about?

[00:27:37]Where B is not four.

[00:27:40]B is 1, two, or seven is in this cage and up here. It's got to be in one of those two cells.

[00:27:48]And now it's in this cage. And I just thought and that would force it not to be here with six because six and B are in this one together.

[00:27:59]Oh, this is far far simpler.

[00:28:05]Oh, is it far simpler than anything I've been saying? No, I was about to announce that this is six and B in some order and curses. I can't do it because of this possibility of B being four, right? I want to eliminate that possibility somehow. Why? Why oh why can B not be four? This would be a a 4 six cage.

[00:28:40]B would be four. Red would be one.

[00:28:56]That would be red one. And this would be six.

[00:29:02]And there'd be a six in one of these cells.

[00:29:09]Six is not that powerful a digit because it could be in a cage still.

[00:29:17]Oh, there were these two possibilities and I cannot juggle them enough in my head to work out what's going on. I'm sorry.

[00:29:33]354.

[00:29:38]This is 2, six or seven. So yeah, I'm I'm reluctantly forced back onto the there is a possibility that B is four and in this cage which is a a 46 cage then and then this would be B.

[00:30:00]So B would be well sorry four. Yeah, four would be B in these positions.

[00:30:06]One of those two. Yeah, let's let's try and take this a bit further around the grid.

[00:30:12]We don't know what color this B would be except well it would be one of these colors. A blue, light blue, pink, or violet. So as a four, it couldn't be in gray. Therefore, it would be in one of those cells. And then we would find out actually.

[00:30:32]No, hang on. Why am I keeping it out of that blue cage, the double blue cage?

[00:30:42]I've got no right to keep it out of that cage.

[00:30:46]It's not a digit that can't appear in a cage yet.

[00:30:51]I'll bother.

[00:30:55]Right. This puzzle proceeds very nicely.

[00:30:58]either with the conclusion that B is four and sitting here and here or with the conclusion that B isn't four and the other digit here will go in this cage and that becomes a six.

[00:31:16]I think this cell because of those possibilities this cell is either one or six. either B is four in this cage or B is 1 2 and seven and can't appear here and this therefore it must appear in one of these cells and it can't appear with the six from this cage there. So I think this digit is one or six and I wish that gave me something. I really do.

[00:31:51]Okay. If this if red is four, that's a four. That becomes four.

[00:32:01]Okay. That No, I don't know. This is one or six.

[00:32:10]If it's one, that's six. Then this row is 614 57 three or nine there.

[00:32:29]I don't know. I'm I'm probably meant to be thinking about a different cage. This one for instance, which there is a lot of action in it. It's either three and Well, it's three and either 4, 6, 7, 8, or 9 by Sudoku.

[00:32:51]Now, it's not three and six because they're both in this cage. So, actually, I can delete six out of that cell. Six is in one of these.

[00:33:01]That's quite interesting. If this digit is six, six is in one of those two. It's there.

[00:33:10]Then it's in one of these two and one of these two. And given the other sixes we already know about this digit would become in fact this digit is six. We know six is in that cage. This can't be six. This is six and it's not yellow.

[00:33:29]Yellow is now in one of those two. I mean that's not going to change the world but it is quite interesting.

[00:33:36]If that was yellow, yellow in row eight is in one of those two and one of these is yellow.

[00:33:46]Alternatively, that's yellow.

[00:33:54]Okay, I'm going to try and think about something else. I know I've got a bit fixated on certain things here. Two and eight in column 7 have to be in one of these each in one of these three cells.

[00:34:10]or maybe seven in this row. Can seven be?

[00:34:16]Look at the sevens we'd have placed in the grid. Quite a few of them straight away.

[00:34:27]Um, but not enough. This digit by Sudoku is 78 or 9. This is 278 or 9.

[00:34:41]This is not six. So this is 1 8 or 9 which looks a bit like that. So if this was one, this would be an 8 n pair. This digit would be 2 or 7.

[00:35:02]That 8 n pair. Is that interesting?

[00:35:10]I don't know. I don't know.

[00:35:23]Just Oh, red. Um, one of those is red.

[00:35:32]Red is one or four. So down here, red has to be in one of these two cells.

[00:35:38]I have never seen that before.

[00:35:41]Now red is in one of those two cells in row seven.

[00:35:47]Don't think it's really doing anything, but it's quite interesting.

[00:35:59]almost means that these are three and seven if this was 1 145 and it does include yellow and red. So it could be this would be a three seven pair.

[00:36:13]Yeah. I know. I don't know. I'm just speculating wildly now. I just got so little to go on. Um, I was about to proclaim that this digit must be in one of those cells, but it's nonsense. It could easily go in that cage.

[00:36:36]So, this cage we just worked out. It couldn't be 3 six. Is there anything else? It can't be here. Well, it's impossible for it to be 3 1 or 32.

[00:36:54]So, it is either 34, 37, 38 or 39.

[00:37:05]Now, whichever one it is, threes in this cage, the 478 or 9 would have to be kept outside it.

[00:37:14]And it couldn't be red because red's not allowed in that cage.

[00:37:18]So this digit, this is either 3 A and 3B. And the A or B in question is 4 78 or 9, but it could overlap with the B down here, whatever that is. I mean, I could call that three and C, but C could be the same as A or B, as far as I know.

[00:37:48]Seven by Sudoku is in one of these three cells in the box. If it was in with the Let's have a little dabble at seven and three being in the cage.

[00:37:59]Seven will be in one of those cell. In fact, this will be seven. That's seven.

[00:38:04]One of those two.

[00:38:06]Oh, that seven is looking directly at this. So, A can't be seven.

[00:38:11]Does that mean it can't be in this cage?

[00:38:14]What does this consist of? A and what else?

[00:38:18]A and something that's in here. That doesn't mean seven's been ruled out. A itself can't be seven, though, because of this. Obviously, six, five, seven. Oh, goodness. It's very, very hard to get to grips with this puzzle. I'm going to say that. And I I defy anybody to just whip through this. It's really a thinker.

[00:38:53]Okay, I'm going to think about this because I've only just considered this this digit.

[00:39:01]If it's two or seven, which it might well be, it can't go there. and it's not able to be in these cells. It would have to be in this cage. Then that digit would not be allowed in the same cage.

[00:39:16]If this is two or seven, this digit has to be in one of those and literally has to be a four.

[00:39:29]Oh, something interesting just happened there when I wasn't expecting it. If this is two or seven because of the business here that I just explained, this has to be a four and then this is one.

[00:39:49]So this would be a 1 14 in that case. If alternatively this is a six, all that's left here is a 1 14 pair.

[00:39:59]So, in all circumstances, this pair that I'm on here is a 1 14 pair. This digit cannot be a six. But I think there has to be a six in this cage. And now we've found it. It's there. This is B. B is a one or a four. That is there.

[00:40:15]And that is a pair in the row. And we can't have a one in this cage with A in it. And we can't have a one there.

[00:40:25]I mean, I don't know how that happened, but it happened. I think it was definitely right. It was dependent on this digit and then putting that into one of these cells and not being allowed to put that into that was right. Okay.

[00:40:40]Well, that I don't know if that was easy. It didn't feel easy. Two and seven in this row are now in these cells and this digit is three or five by Sudoku or whatever.

[00:40:56]This is a one four pair and it includes red and B these two cells.

[00:41:08]Well, now now we have to start going.

[00:41:14]This cage contains three and some digit that's not in the Z pentomino. It doesn't contain three and one by Sudoku. So, it's either three and four if that's allowed and I think it is at the moment or three and five not possible or three and two not possible. So this is either 34, 38 or 39. This digit can't be an eight by Sudoku.

[00:41:47]And whatever digit is in this cage with three is either B or that digit.

[00:42:00]Now what about this one four pair?

[00:42:04]One of these is a one.

[00:42:06]I doubt that I can get much more out of this, but two is now in one of these two cells in the bottom row.

[00:42:15]Seven. Oh, I don't know. It's still in one of those three. I thought thought I knew something about seven. I blooming don't. Um, that digit is eight or nine. There's just nothing else it can be given everything it sees in the column. This six feels powerful suddenly.

[00:42:42]What am I meant to be doing with it?

[00:42:48]Ah, I don't know. I can't see. Can gray be six?

[00:42:56]Probably. I don't see a reason why it can't be. Well, I mean, that was so interesting. That was just this cage doing something.

[00:43:05]And I barely even know what it was doing, but it did it.

[00:43:15]Now, that was a weird moment, right? Red is one or four and goes in one of these cells.

[00:43:27]Still don't know which. Oh, this what about this cell?

[00:43:44]I don't know.

[00:43:46]It could be this red if if it's four.

[00:43:54]Yeah. I mean, maybe that's the case to be thinking about. What is this? What is this? This is well okay these two digits. Oh, I was going to say they have to be fitted into this column.

[00:44:09]And I was hoping to constrain them to this cell and one other. Well, that one and that one, but this digit could be a one. Okay. So, let's try and falsify that. If this digit is a one, this is a six and red is a four.

[00:44:28]Ah, that that's instantly falsified.

[00:44:30]Fantastic. If this digit is a one, it sees that red is a four. That's a four.

[00:44:36]And they both see this cell and it has no fill. So that's not a one. This is now an 8 N pair. Now there was some reason I really liked that. It keeps 8 N out of that cell. And that wasn't the reason. What was the reason?

[00:44:50]It was something to do with some other digit having to go in here. Or no, maybe it was forcing an eight or well maybe there isn't another reason why I should like it but it just felt like there was these include a which is that has that got narrowed down and then it has to appear here and it's either 278 or 9.

[00:45:12]Well, it's not 7 A. So A is 28. Oh, I know that here A is 28 or 9 and it's in one of these cells.

[00:45:24]And whatever this other digit is, a cannot be with that here. Ah, so if a was a two there, it would be a two here and it would have to appear here. The same is sort of true for an eight.

[00:45:46]No, but that's a good place. A is happy with that.

[00:45:53]Maybe I can say this isn't eight. It would have to be nine and it would be there and there.

[00:46:00]And then this other digit that's two or seven would not be allowed in the same cage in box six and would have to go there. But that could be a two.

[00:46:13]I think this cage can't be a 97 cage now, which is a weird weird weird um calculation, but it's true. And it doesn't do anything. It doesn't do anything. I just barely understand how I got this one four pair. We've got 2789.

[00:46:34]That's why I was liking this.

[00:46:37]This digit is four, five, or six.

[00:46:41]These ones are a three five pair. They see 27 89 and a 146 triple. They are a 35 pair and this digit is not five. It is four or six. And we did find our 146 triple which I thought we sort of might.

[00:46:58]Did I? Yeah, I'm going to claim I did think we might.

[00:47:05]Okay. So, if that's a four, that's a four, that's one, that's six.

[00:47:11]Ah. Uh, no. Then this is a one. Yeah, this is either a one six or a 46 cage.

[00:47:18]Now, where is that very very significant?

[00:47:22]Is it up here?

[00:47:29]Oh, five in this top box is in one of those two cells. That's strange.

[00:47:37]It doesn't do anything. I should think about this. Maybe this cage.

[00:47:49]I can't even say that B is definitely in this cage because B could be one and be sitting there. No, it can't. This is B.

[00:48:00]Since that became six, this is B by Sudoku. B is ruled out of both of those cells, all of these four cells. So B is definitely in one of these two and one of these three and it's one or four. So it's got to be one now. B is one again. I don't quite understand how that fell out, but it did. B is one. And now red is four and has finally been determined after 49 crazy minutes. That digit is a six. It's not red. This digit is red. It's a four.

[00:48:39]This digit is not red as well, right? There's a four down here because we know red is a four. Now, can we actually get on our horse and get something done? This is not a six. These that include B are from 127.

[00:48:59]One six is not allowed in any other cage as a pair.

[00:49:07]What good is that? Must be some good.

[00:49:10]These are from five, six, eight, nine.

[00:49:12]That one can't be five.

[00:49:17]Three, four, five.

[00:49:20]These digits are the the other digits from 27 89. So that's 2 eight or nine. This could be any of those. A. Now let's focus on A.

[00:49:34]A is 2, eight or nine and in one of those cells and in one of these two.

[00:49:45]Or no, maybe let's focus on this cage which contains three and a digit that is either four or is a so that it doesn't all fit in this box.

[00:50:05]No, I don't know. Right. If there's a four in one of those two, there's a four in one of these. Four cannot be in this cage because four is red. Four has to be in one of those two cells. And now it's in one of these two and is an X-wing with this pair. Right?

[00:50:29]That cage now contains either 3 9 or 38.

[00:50:34]Are either of them? Yes. That forces 9 or 8 into this cell because three is in this cage here. Thus, A becomes 9 or eight and that can't be A anymore. A is definitely here.

[00:50:52]And it's in one of these and is eight or nine. It's either nine here.

[00:50:58]Ah.

[00:50:59]Okay. I don't know whether it's which cell it's in. I don't know whether it's eight or nine, but it's the second of eight or nine in this row.

[00:51:09]So, none of these can be eight or nine.

[00:51:13]Okay. I'm going to call this C. It's the other digit in eight or nine. It's a for form of coloring.

[00:51:21]And C is in one of those cells and one of these three. And that maybe isn't doing anything.

[00:51:33]Oh, um, a I don't know. This was going to be three and a. So a is in one of those two cells and it's in one of those two.

[00:51:47]And now it has to be in one of these three. But that includes this cell where I can't even mark an A due to the given.

[00:51:54]And it could be nine.

[00:51:57]A is in fact not three. It is eight or nine. Well, it's in one of these. It can't be eight. A is nine.

[00:52:04]Right? That is a three nine pair. A is nine. It's in this cell.

[00:52:09]Wow. Okay. A is nine. C becomes eight.

[00:52:14]These can't be nine anymore. That is a three nine pair. I don't know the order.

[00:52:21]Do I know the order? I don't think I know the order. But still this can't be nine. Now 9 and 8 that 8 has to go in one of these two cells in the central box.

[00:52:35]41 95. This cage this is really crucial.

[00:52:39]This contains 2 3 6 7 8. So look at a cage like this. This can't contain two of those.

[00:52:47]And yet 2 3 and 8 are still to be determined.

[00:52:56]Well, this cage can't contain two and eight. So, the other one from 2 eight must be here. And one of these two must be a three.

[00:53:06]Otherwise, that would be broken. Yes.

[00:53:09]Now, this is nine. That's three. And A is nine. Now, yeah, we know I've done that, right?

[00:53:18]This digit C is nine.

[00:53:22]Um, this digit sees nine. What is a? A is nine. So that is a nine. Yes, that's just sudoku. Now get rid of the a.

[00:53:33]Right. This cage is nine and two or eight. Is that threatening to fill some other cage? I mean, there's not many cages left, weirdly. Now there's kind of these two.

[00:53:47]And okay, I know that one of them contains a one and one of them contains a nine. Right, that's become a one nine pair in those cells because of these ones and nines preventing these cells having a one or a nine. That's weird.

[00:54:02]That gets them into the extremities.

[00:54:06]Now, the other digit is obviously from this cage. 1 945. This column, this digit sees two seven in the box and six.

[00:54:17]This is three or eight.

[00:54:20]This one can't be 1 945 or 8. 2 3 6 or 7. This one 945 and it sees 37.

[00:54:29]So, this was the more exciting one. This orange, green, and gray coloring never went anywhere, did it? Never mind about that.

[00:54:38]Now, where are we now?

[00:54:43]yellow.

[00:54:47]Yellow five is in one of those cells and one of these to I don't know why that coloring wasn't marked earlier or whether it's worth doing now.

[00:55:02]Nine and that digit can't be one of these makeups.

[00:55:10]This is by the way 67 or 8.

[00:55:14]And this one 416 985.

[00:55:19]This is 2 3 or 7.

[00:55:25]So this cage consists of one or nine plus 2, three or seven.

[00:55:36]This is wrecking my head. Um, I bet there's one of these little cages and I can tell if I just think about it what's going on.

[00:55:49]I mean, obviously that digit can't be that. That's just sudoku.

[00:55:58]There's loads of two cell cages with nine in, aren't there?

[00:56:04]And one of these does the same, right?

[00:56:08]Uh I suppose I know that 93 can't be a cage here.

[00:56:16]Depending what this one and this one are, I could rule out 92.

[00:56:22]Two out of 92, 97, and 98 as well.

[00:56:29]One six can't be in a cage together. So that couldn't be up here. I mean that this is it's this is the trouble with the rule in a way. It's so complicated to work out the little bits and bobs around it.

[00:56:46]Oh, this digit is 7 8 or nine cuz it sees 1 2 3 4 5 six.

[00:56:53]But two is in one of those two cells.

[00:56:57]I need more cages.

[00:57:02]But we're getting there. We're getting there. I'm fascinated by this. I am persevering with this one. 4195. We know that 8 is in one of those two cells. And one of those two.

[00:57:22]Oh, look. These don't have that's not a four. This is a one three pair. So this cage consists of one, three, and either two or eight. Is that how to use that?

[00:57:43]Oh, maybe there's a a play between these.

[00:57:48]I probably would need to have solved a bit more Sudoku to use that if there is.

[00:57:54]Oh, look. Seven can't go here. Seven's in one of those two cells and that is just sudoku. But then seven is in one of these three as is four in one of those two. So why shouldn't this be seven? Let's just have a ponder about that.

[00:58:19]I don't know.

[00:58:23]Oh, seven is also looking at this cell and has been forever.

[00:58:35]So, ooh, if this cage was 278, wouldn't it be a constituent, a subset of this cage?

[00:58:45]It would. So, there has to be a one in these cells.

[00:58:50]Oh, that that was obvious by Sudoku.

[00:58:52]That is not an interesting finding. I apologize.

[00:58:56]I thought it was. It wasn't. One in this box is in one of those two.

[00:59:04]That also feels far from interesting.

[00:59:09]Four. Five. Did three get confined? Oh, three did get confined in this box to one of those two. And that's an X-wing. So this group of cells, oh this has become a five. That's the point that I couldn't see.

[00:59:26]That's quite important. I imagine this group of cells is 237. Now that makes this orange cell an eight.

[00:59:37]And now we take eight out of those two.

[00:59:41]2 3 786.

[00:59:44]Nine is in one of those two. That feels analogous to what I did with one up there. These are from 145.

[00:59:55]237. So this cage got narrowed down a bit. Is something impossible there? If that was 97, this wouldn't be allowed to be 97.

[01:00:07]So if that was No, that doesn't mean if that was a nine, this would be a six. It does not mean that.

[01:00:14]If this is a one, this can't be a three.

[01:00:18]Ah, this can never be a three this cell because it's either a 93 cage and we've had one or a three cage and it would break there. So, this can't be a three.

[01:00:29]And now this is a 27 pair and this digit is a three.

[01:00:34]And now the central cell is a three.

[01:00:39]And now this digit I want to say it's a six. That might be wrong. 435. No, we don't know that. It's still two or six.

[01:00:47]That central digit being a three places one and three over here. I am going to get rid of those colors. They were never really in play.

[01:00:57]Um, we've got this 28 pair.

[01:01:04]Four and seven are in use. No, let's go back down here. 27836.

[01:01:10]That is four, five or nine. That's not interesting. This cage in this row, that can't be one. That's interesting because this digit is now one.

[01:01:22]And that digit is 2 or eight to complete the row. These are from 267.

[01:01:30]This one can't be six. We can find six in this central row. Now there.

[01:01:37]And now one of these two is six. Now, can we pull the same sort of trick here?

[01:01:43]This can't be a one six cage because of that.

[01:01:52]Come on. 96 or something or 17. Why couldn't it be 17?

[01:02:02]Almost because of this. Okay. It can't be a one six cage.

[01:02:14]So either that's one or that's six. How do I use information like that? That is weird information.

[01:02:23]Okay, let's come back to this one in case we can do more there.

[01:02:30]If this was one, two, that would be an eight.

[01:02:44]Oh. Oh. Oh no. That's interesting. If this was one two, that would have to be 17. This would be 92.

[01:03:01]I can't work this crazy puzzle out. Um, these are from 137 593764128.

[01:03:15]I haven't speculated about in this box.

[01:03:25]My goodness. I still don't know how these two work. One of them's got a one and one of them's got a nine and that's obvious.

[01:03:34]315 46. One of these two is a two. It's all about these. Oh, didn't I work out?

[01:03:41]Did I work out what B was at some point?

[01:03:46]Wasn't B one of these two? They were A and B, weren't they?

[01:03:52]Is that right? No, they couldn't have been. In fact, that was B. B was one.

[01:03:58]That's why this saying B doesn't help.

[01:04:02]Okay, let us color two sevens against each other. I don't think it's going to do anything, but I've got very few shots in my locker.

[01:04:16]That is a pair of them.

[01:04:20]So, one of these is green and one of these two is pink.

[01:04:27]I shouldn't have used pink because I've got pink going somewhere else.

[01:04:31]I should have used green and gray.

[01:04:33]Sorry. Um, and that one was gray, wasn't it?

[01:04:40]Two and seven. So, one of those is gray, but we just don't know with green. One of these is green.

[01:04:51]I don't know. That does that doesn't do anything, does it?

[01:04:59]Okay. Maybe it's just to do with these relationships and these. Although the trouble with that is nine must go with whatever is not two or seven there. So it can do it here. But that would always be a 27th pair of different digits.

[01:05:17]Well, that's quite interesting actually.

[01:05:26]So, what I'm saying is if this is nine, this isn't allowed to be gray. This would be green, and that would be gray here.

[01:05:39]So, if we had a nine at the bottom of the grid, the cells I'm now highlighting would be gray.

[01:05:49]I don't know. I don't know if they're Oh.

[01:05:55]One of those two.

[01:05:59]No, it doesn't. It doesn't get anything done.

[01:06:04]So, is it this stuff?

[01:06:06]One. If that was a two, if that was a two, this would be eight.

[01:06:28]Maybe I should do then if this was eight.

[01:06:34]If this was eight, we'd have a two there and a two there. We'd have both 92 and one two in a cage.

[01:06:43]And therefore, this would have to be two.

[01:06:47]So if row 6, column 7 was an eight, we'd get twos in these positions. Now highlighting there obviously that's where it sort of started and there would get twos in all those positions.

[01:07:11]Okay. Um I'm going to label them as C.

[01:07:16]If alternatively this is a two.

[01:07:20]Now, do we know then where twos do go or do we really not? Two is in a cage with a one at that point. So, this can't be Oh, no. 123 in one cage and 128 in another. That is perfectly legal because there's no subset going on.

[01:07:44]That's vicious in a way. I mean, there's probably only one thing that I've got left to see in this puzzle, and I'm finding it very difficult. And I mean, obviously, that's true.

[01:07:56]I don't know how to do it, but I am just going to keep working on it. Right, these two, if they were the same, that digit at the top is going to have to be a one. Then, if they were the same, they'd be sevens.

[01:08:16]So, we'd have another one here and here and here and here and one of these two and one of these two and we definitely have one there.

[01:08:30]So, if those two digits were the same, we'd have to have a one at the top and a nine at the bottom.

[01:08:47]And the nine would be in a 92 cage. And this would be an eight. And that would be a two. Oh goodness. This is wildly complicated to study.

[01:08:59]And I don't think it falsified. I I couldn't see where it did. I can imagine that there's a look a sort of chain like that somewhere that we could visualize.

[01:09:09]It might be a very short chain. I admit that. But I haven't seen what it is yet.

[01:09:18]It's probably something very simple.

[01:09:20]What can one go with in these?

[01:09:25]Because it mustn't go with whatever either of these digits are.

[01:09:34]Yeah. Okay. So, what do they narrow down to? If this one's a seven, that's two. That's eight. That's two. So if this is a seven, that's a two. Oh, and then one couldn't be here because it would go with seven or two. That's quite interesting. So if that's a seven, this is a two. And now this has to be a nine at the bottom.

[01:10:03]And a one at the top going with a six.

[01:10:11]So the seven in the middle row in the middle column I mean would have to be here right?

[01:10:20]What was I saying if that was a two?

[01:10:28]Didn't know I didn't say that. I said if this was a seven.

[01:10:34]Yeah. I said if that was a seven.

[01:10:37]So I'd be forced to have a seven here.

[01:10:39]Then now what happens to that? We get certain sevens that are positioned in the grid, including a 97 at the bottom and a 17 in the other cage. We'd have Oh, this Yeah, that here's why that doesn't right. That doesn't work. Okay, let me take this take you through this again.

[01:11:17]If this was a seven, that's a two. This is eight. That's two.

[01:11:27]Now we've got one and two in the same cage. And this couldn't be one, two, and one and seven in the same gauge. So this would have to be nine.

[01:11:37]And you've got a one here which couldn't go with a seven. So that would be one six. The seven in the middle. Well, one six is impossible because of that one six cage. There we go. So this can't be a seven. But that is a complicated chain. This is a two. And I think we're in business now. This is a seven. This is a seven. That's just Sudoku.

[01:12:02]Um this is not a seven.

[01:12:06]Now, I said we're in business, but maybe we haven't actually finished anything. We can take seven out of those cells.

[01:12:19]If it doesn't deal with these central columns at all, that will be quite irritating. But still, two there means no two in the corner means two here.

[01:12:29]Now, I had that labeled as C earlier, but I don't trust myself on that.

[01:12:35]That might have been continue. No, I had those all labeled as C because they were the output of some theory that I never used.

[01:12:44]So, we forget that theory.

[01:12:48]That pair doesn't need a corner mark anymore. Um, right. I I know I haven't finished at all, but I've got closer.

[01:12:55]I've got a cage with 128 in it.

[01:13:00]And I therefore know that this can't be a one two cage.

[01:13:07]And we can't have a 97 cage in either place. So the seven must go with a one in one of these.

[01:13:18]And the nine will either go with a two or a six. So there's going to be a seven cage.

[01:13:26]That doesn't interfere with anything else. We're either going to have 92 or 96.

[01:13:39]Still not done. Oh, hang on. Eight is looking at that cell. I don't know how long that's been available for. Eight there, six here, seven here. That makes this a two. Now, what did I just say? 2 one is not possible. So that's 2 nine.

[01:13:54]That's a one. That's a six. We were going to have a one seven cage. I think that's what I said before.

[01:14:02]So here we go. I think we're on the last leg now. That's a seven.

[01:14:09]We've had two nine in a cage. So this can't be 29. That's an eight.

[01:14:16]Wow. I really hope this is right and I haven't botched something else.

[01:14:22]Goodness me. Absolute puzzle. Right, that's not a nine. There's a one in one of those cells. 3 2967 1. Oh, what have we got up here? A 48 pair that I can just fill in. Actually, what I could do is remove the non red bits. That wrong.

[01:14:48]One of these two is still No, that can't be red because of the red down here. So, it's not four. This is where four goes now.

[01:14:58]That's a five. That's a one. That five gives us three and five. Okay. Bye-bye yellow coloring.

[01:15:12]I don't know. Bye-bye coloring. Bye-bye.

[01:15:16]Bye-bye gray. You know, green and gray, you were never doing much.

[01:15:22]I'll just get rid of all the colors, Mark, for goodness sake. Stop faffing around. Right. This is a seven. That's a one.

[01:15:32]This is eight in the corner.

[01:15:35]That's a five N pair. I think I think that's fair.

[01:15:41]That's a five. That sorts out 95. That sorts out 92.

[01:15:48]This is 276. I can do the two. Yes. Then I can do the seven. Then the six. This is 148. I can do the 1 4 the8. And these are 347. And I believe that is the solution to this remarkable puzzle. Busy busway. 7717 and a 17 cage in my time there because we had a 17 cage towards the end there.

[01:16:13]Wow, what a remarkably interesting puzzle. I don't want to do another one like that soon cuz it really was difficult. It really stretched me. But I've had a good time. Thank you so much for watching. Do leave a comment. Tell me if I was just unbelievably slow at spotting things. To be honest, when I did spot things, it didn't feel like I'd been missing them for a for a good for a bad reason, but I might be wrong. I'll see you soon on the channel, I hope. Bye for now.