Learn How To Sudoku with Gone Fishing

Added: 2026-05-21

[00:00:01]Hello everyone. I'm Frank and welcome to learn how to sedoku where we take a very easy variant sudoku puzzle and we break it down in detail so that you can learn how to sedoku.

[00:00:14]Today's very easy puzzle is called gone fishing by Darth Silius 72.

[00:00:21]And here are the rules we have. Normal Sudoku rules apply which means in every cell in the grid place a single digit from 1 through 9 such that there are no repeats in any row column well we can get a column here and designated nine cell region.

[00:00:41]In addition a digits digits a chess knight's or a king's move apart must be different. So there are no repeats in cells that are a kings move apart or knights move apart. So that means in a for this cell say whatever this digit is you cannot have repeats in the same row column or box.

[00:01:07]But you can also not have repeats in any cell that is a king's move apart or a knight's move apart.

[00:01:16]So that means these cells also cannot have the same digit as this one because this is a chess kings move apart and this is a chess knight's move apart for these.

[00:01:32]Also we can't have digits repeat within a cage. So there are no repeats within a cage here.

[00:01:41]Each set of three digits along the orange line must contain one digit from 1 2 3, one digit from four, five, six, and one digit from 7 8 9.

[00:01:54]Um, so as an example, you could have something like say 6 9 and 1. And that would be valid um for three consecutive digits on this orange line.

[00:02:11]And this would work because we have one digit that's low, one, one digit that's middle, six, which is six or yeah, one digit that's middle, which is a six, and one digit that's high, which is the nine.

[00:02:23]And this is known as an entropic line.

[00:02:29]Um, and we have digits separated by an X or V sum to 10 or five respectively. And digits separated by a black dot are in a 1:2 ratio. And not all XV or black dots are necessarily given. So as an example, if this were say three, this would have to be seven because they must add up to 10 because there's an X between them. If this were say four, this would have to be one because these must add up to five because there's a V between them. And if we had a two here, this would have to be one or four to maintain the 1:2 ratio because there's a black crop key dot that's between them.

[00:03:12]And those are all the rules. If you like to play along, there's going to be a link in the description. And now I'm going to get started.

[00:03:22]Let's learn how to sedoku.

[00:03:26]Okay.

[00:03:28]Um, we know so these this is nine cells in this cage, right? 1 2 3 4 5 6 7 8 9. We cannot have cells be the same which are in kings or knights move apart.

[00:03:50]Um, so let's color each of these cells.

[00:04:03]Um, so we're missing in this cage the pink cell, the medium cell, and the dark cell. The dark cell cannot be any of these. So where is the dark cell? It must be there. The pink cell cannot be here because of chess knight's move. So this must be pink cell here which means the last cell here is medium. Okay.

[00:04:28]Um so if ch if cells can't be a chess knight chess kings move apart or chess knights move apart this dark cannot be here or here. Where is it in row five?

[00:04:40]It can't be here because of a dark in the box. It can't be here because of dark in the box. And these this is not allowed by kings or knights move. So this must be dark here.

[00:04:53]Um yeah and any cell on the edge cannot be a kings or knights move apart which means this cell cannot be here or here.

[00:05:04]So anything in the middle is necessarily going to have to be one of these two cells at the end. So this is not here.

[00:05:12]It's not here. It has to be one of these two.

[00:05:15]Green has to also be one of those two.

[00:05:20]Um, this digit cannot be the same as any of these. So, it has to be light or red.

[00:05:34]Um, this cannot be any of these cells here.

[00:05:39]So, it's dark. It cannot be dark. It has to be blue. So this is blue. That's helpful.

[00:05:46]This can't be any of these cells. It can't be medium. So it's light or dark.

[00:05:50]It cannot be dark because that's a night's move away from that cell. So this must be light.

[00:05:57]How about here? This can't be any of these cells. It has to be red or blue.

[00:06:02]So this is red or blue.

[00:06:07]This cell cannot be all of these. Can't be any of these because of king's move and knight's move. So it has to be yellow, red or blue here or sorry yellow, red or green here.

[00:06:22]Also, where's the blue? Blue can't be here because if it's knights move apart.

[00:06:26]So blue has to be one of those two.

[00:06:29]Remaining colors in column six we have light, no medium, no dark, green, no pink, no orange, red and yellow. Okay, so we have light, medium, pink, like medium, green, and yellow. This can't be light because that's a knight's move from this cell.

[00:07:05]remaining colors. In row six, we have light, medium, no dark, green, pink, and orange.

[00:07:27]Again, this can't be green because of knight's move.

[00:07:32]This can't be pink because of knight's move or orange because of king's move.

[00:07:39]Um, this can't be medium because of that knight's move. This can't be light because of this light's move. Okay, so this is green, which eliminates green in the rest of the row. So, where is green in row in box in this left hand box, left central box here? It has to be there.

[00:07:58]This can't be orange because of knight's move. This can't be pink because of knight's move. So, this is medium or light.

[00:08:12]Okay.

[00:08:17]Remaining colors in row five we have light, medium, um, red, and yellow.

[00:08:32]Okay, this red eliminates red here by knight's move. This can't be light because of the knight's move from there.

[00:08:43]Um, this could be any of them.

[00:08:48]This could be any of those.

[00:08:55]Okay. Um, column six, what are the possib or column five, what are the possibilities? No light, no medium. We have dark, we have green, no pink, we could have orange, red, and blue. So, no red or blue here because of knight's move.

[00:09:16]Um, this is blue or red. This can't be dark because of night's move.

[00:09:33]Um, I think that's pretty much it.

[00:09:35]Unfortunately, let's do rest of row four.

[00:09:42]We already got the blue. So, no green. We have pink, orange, red, and yellow left.

[00:09:54]Okay. So, pink cannot be here or here because of knight's move.

[00:10:06]Red can't be here because of knight's move. So, we have yellow or orange there. Orange cannot be here because of king's move and can't be here because of knight's move.

[00:10:20]Um Uh, does this help us any really?

[00:11:17]This can't be light because of light in the reg in the box.

[00:11:28]Um, uh, column four.

[00:11:33]We could have medium, dark, pink, orange, yellow, or blue.

[00:11:40]Okay, this can't be medium or dark because of king's move and knight's move. No blue because of knight's move.

[00:11:46]No pink because of knight's move.

[00:11:50]This can't be medium because of knight's move.

[00:11:55]This can't be yellow or blue or dark because of of kings or knights move.

[00:12:00]This can't be pink or medium which means this is orange. Okay, that's good. Which get lose eliminates orange from the rest of the column and box.

[00:12:17]Okay, this is yellow which eliminates yellow from the rest of the column and box.

[00:12:26]Okay, this is yellow which eliminates yellow from the rest for king and knight's move here. So this is orange here which eliminates orange from the rest of the box and row. So no orange there.

[00:12:46]Um, where is orange in row six then? It must be here. So that's orange.

[00:13:00]We have the we have a light medium pink triplet in row six. This therefore this must be pink here which means this cannot be pink here. It's red. that eliminates a red in the rest of the box and the that eliminates red from the rest of this row. So this is yellow which means this can't be yellow here.

[00:13:24]It's blue pink as a pair. Yellow eliminates yellow here as a possibility.

[00:13:32]Where is yellow remaining in column six? It has to be here.

[00:13:40]This is green, red, and light as a triplet here, which eliminates green, red, and light in the rest of the row.

[00:13:46]So there's no red here.

[00:13:49]That means this is blue. There's no green here. And blue eliminates blue as the rest of in the rest of the box. So this is orange, which means this can't be orange. That's dark, which means this can't be dark. That's pink, which means this can't be pink. So that's medium.

[00:14:05]Dark eliminates dark in the rest of the column. This can't be dark. It can't be green or blue. It's red.

[00:14:14]Pink and medium are eliminated here because they're in the box. So, this is a blue dark pair. Dark can't be here because of knight's move from that al.

[00:14:23]So, this is blue, which means this can't be blue. That's dark.

[00:14:29][snorts] Um, this is green, red, or light.

[00:14:38]Okay.

[00:14:47]Yellow cannot be here or here because of yellow's in the in the row and column.

[00:14:53]Can't be here because of knight's move.

[00:14:58]Um [snorts] um let's do remaining. This is basically just a coloring exercise. Um let's just do remaining digits in row six.

[00:15:25]We can't have light. We could have medium, dark, green, no pink, no orange, red, yellow, blue.

[00:15:34]Okay, let's eliminate possibilities.

[00:15:37]This can't be blue or dark because they're in the same column. Can't be red because of king's move. Can't be anti- king, I should say. Can't be yellow because of anti-night.

[00:15:49]Can't be green because of anti- knight.

[00:15:52]So this is medium which eliminates medium in the rest of the row.

[00:15:58]This can't be green because of in the same column. Can't be blue because of anti- king. Can't be yellow because of anti- knight.

[00:16:08]Um one of these is going to be red. So if this is red, that would eliminate that from normal sodoku. That would eliminate that because of anti-ight. So this cannot be red. It's dark, which eliminates dark from the rest of the row.

[00:16:23]This can't be blue because of anti- knight. This can't be green because of anti- king.

[00:16:31]This can't be blue because of anti- knight. And can't be red because of red in the column. One of these is going to be yellow, too, which eliminates that cell from being yellow. Because if this were yellow, that it sees that in the same row or column. If this is yellow, anti-night removes that from being yellow. So this is green, which eliminates green in the rest of the row.

[00:16:55]Um, this is also seen by the red here, right? Because if this is red, it's seen by in the same column. And if this is red, it's removed moving removing red because of anti-night. So this is yellow, which eliminates yellow in the same um row. So this is blue or red. We have blue or red there.

[00:17:19]Okay.

[00:17:23]Um this is medium which eliminates medium from these cells here because of anti- king and anti-night which means where is medium in this left central box? It must be here. That eliminates medium here. So this is a red light pair. Therefore, this cannot be light. It's medium.

[00:17:53]Okay, let's continue. Remaining colors in row eight.

[00:18:05]We have light, no medium. It could be dark, no green, pink, orange, red, yellow.

[00:18:14]Obviously, these can't be dark because of dark in the box. This can't be yellow because yellow in the box.

[00:18:23]This can't be dark because of the dark in the column. This can't be dark because of anti- night from that dark.

[00:18:29]So, this must be dark here.

[00:18:32]This can't be yellow or red because of yellow or red in the column. This one of these. So, both of these are pink and light and they both see the cell. This by normal Sudoku. do this by anti-ight.

[00:18:45]So this cannot be pink or light. It's orange which eliminates orange in the rest of the row. So now we have a red, pink, light triplet, which eliminates red, pink, light in the rest of the row.

[00:18:57]So no red, pink, or light here. It's yellow.

[00:19:01]Um this red, pink, or light triplet eliminates red, pink, and light in the rest of the box, too. So this can't be red. This is blue, which eliminates blue here. So that's red. Blue eliminates blue here. So that's pink, which eliminates pink here. So that's blue.

[00:19:16]This can't be red or light because of anti-night rule set from these two cells.

[00:19:24]Wait, that's but that's anti- king is not going to work either. What just happened here?

[00:19:33]Ah, I kind of made I must have made a mistake somewhere. I don't know where.

[00:19:41]Shoot.

[00:19:45]Uh crap.

[00:19:49]And this is a knight's move away. That's not going to work.

[00:19:54]Wow. I me really messed this up. Okay, let's get the coloring back.

[00:20:02]Uh that was really bad. I don't know. I don't know where I made the mistake. So that's why it's sometimes it's better just to restart and get your head straight.

[00:20:12]Okay. Again, this can't be dark. We need all nine cells because there are no repeats within a cage. So, this must be dark. This can't be pink because of anti- night. I'm also not very good at anti- knights. Did I Was that right? I'm not good at anti knight because I don't spot them very well. Anti-kings also I'm not very good at. So um this digit cannot be any of these because this sees it um by anti- king. This sees these cells from normal sudoku and anti-ight.

[00:20:52]This one sees it by anti- king and it cannot be dark because of anti- knight.

[00:20:58]So it's light.

[00:21:03]Um, right. This can't be any of these cells here because of anti- king, anti- knight, and normal sodoku. This can't be dark because of dark in the box. So, this is blue.

[00:21:32]Uh let's do column six. So we have light, no medium, no dark, green, no or no pink, no orange, and red and yellow.

[00:21:48]This can't be light because of light in the box.

[00:21:53]This can't be light because of knights move away.

[00:22:01]So that's fine.

[00:22:04]This digit has to be red or blue.

[00:22:08]This digit has to be red or light.

[00:22:13]Okay, I think we got something here.

[00:22:22]Um remaining colors of row six. We could have light, medium, no dark, green, pink, and orange.

[00:22:36]This can't be pink or orange because of king, anti- king, and anti- knight.

[00:22:46]This can't be green. Um, this can't be green because of anti- night.

[00:22:55]Um, this can't be orange because of anti-ight.

[00:23:04]Um, this can't be light because of anti Oh, that's Oh, and it can't be medium because of anti- king. So, that's green.

[00:23:14]So, therefore, that's why that's green.

[00:23:17]So we don't have green here. Green cannot be here. Cannot be here because anti- knight and anti- king. So therefore that's green.

[00:23:25]Okay.

[00:23:32]What else did we have?

[00:23:37]I think we just went through everyone.

[00:23:39]Okay. So well let's continue that then.

[00:23:42]We have light, medium, dark, red, and yellow.

[00:23:49]No red because of anti- night. No light because of anti- night.

[00:23:57]Um, this can't be dark because of anti- night.

[00:24:02]And I think that's all we have there.

[00:24:07]Um this cell cannot be any of these.

[00:24:22]Can't. So this is medium or dark and it cannot wait.

[00:24:32]No. Okay. So this cell cannot be any of these cells by anti-nit or anti- king.

[00:24:36]So it's orange, medium, and dark. Cannot be medium because of medium in the box.

[00:24:40]Can't be dark because that's the anti- king. So this is orange. Okay. So that's helpful. This can't be orange because of anti- night.

[00:24:54]Okay. What about this? This cannot be any of these. Uh can this cell cannot be here because of anti- king and anti- knight normal sudoku anti-night.

[00:25:08]So it has to be orange, yellow or blue and obviously cannot be blue because of blue in the box. So this is orange or yellow.

[00:25:20]Okay, this cell cannot be any of these cells also. So it's also orange or yellow or blue.

[00:25:33]This can't be orange because of orange in the column. So, this must be yellow, which means this can't be yellow anymore here. There's no yellow available here because of anti- king and then yellow in the same box. So, where is the yellow in column six? It must be there.

[00:25:55]So, that's interesting. This digit again cannot be here because of normal sudoku, anti- king, anti- knight. So this is yellow, red or green. Cannot be green because of green in the box. So this has to be red or yellow.

[00:26:13]Okay, that was interesting. Um this digit uh remaining digits in row four or colors in row four. No light, medium, dark, no green. It could be pink.

[00:26:40]It could be can no orange. It could be red, yellow or blue. So this can't be blue because of blue in the box. This can't be yellow because of anti- night.

[00:26:57]So, where is yellow in row four? It must be one of these three, which means this can't be yellow here.

[00:27:07]Okay.

[00:27:09]Remaining colors in column four, we have medium, dark, pink, and blue.

[00:27:19]Pink obviously cannot be either of these because of pink in the box. It can't be medium either. So this is a blue dark pair which eliminates blue and dark in the rest of the column. So this pink or medium medium eliminates medium here by anti. So this can't be pink here.

[00:27:37]Therefore that's medium there. This is blue dark as a pair which forces this to be red green as a pair and this can't be red because of anti-ight there. So this is green that's red. So this cannot be red here because of red in the column that's blue.

[00:27:55]Remaining colors in column five are dark which cannot be here. So dark is here and orange which then has to be there.

[00:28:06]Okay.

[00:28:09][snorts] This is orange which eliminates orange here. Where is orange in [snorts] row six? It has to be here.

[00:28:21]Okay, this medium eliminates medium as a possibility here. So, this is pink or light.

[00:28:29]So, medium in row six must be one of these two, which eliminates medium from here.

[00:28:35][snorts] How did I Oh, this can't be dark because of dark in the box. So this is yellow which eliminates yellow here.

[00:28:45]Um we have a red light pair which eliminates red light in the rest of the row. So no red or light. That's medium which means can't be medium there.

[00:28:53]That's dark.

[00:28:58]Okay. How did I get this so weird anyways? Huh?

[00:29:05]Um, this can't be dark because of anti-ight.

[00:29:12]So, this is blue, which eliminates blue there. I don't know how I got this. So, this is so different. Anyways, um [snorts] I'm just not good at I I think the thing is that I'm just not good at anti- knight. I don't spot them very well or I make some mistakes. Um anyways, [snorts] media dark cannot be here because of normal sodok. Dark can't be here or here because of normal sodoku. Can't be here because of anti- knight. Can't be here because of anti- king from this cell.

[00:29:49]Can't be here because of anti- king or anti- knight. So dark has to be there.

[00:29:55]Dark cannot be here or here in row seven because of anti- uh normal sodoku and anti-night. So dark has to be there.

[00:30:08]Um where is dark in column 8 can't be here because of anti- night. Can't be here because of night dark in the col row. So dark has to be there which means we have eight darks. The last dark has to be there. Okay, we have a lot of orange. Orange can't be here or here because of normal sodoku can't be here because of anti-night. So orange is one of these two which means orange has to be in row eight. Cannot be here. It has to be one of these two because it can't be here because of anti of normal sudoku rules. This can't be orange because of anti-ight. So orange has to be there.

[00:30:51]Um, orange can't be here or here because of normal Sudoku rules. Can't be here because of anti-Night from that cell.

[00:31:00]So, orange is one of those two, which means this can't be orange in column 8.

[00:31:05]It has to be here.

[00:31:10]Okay. What about yellows, blues, greens, reds?

[00:31:25]Um, let's just fill out cannot be light, medium, or dark. It has to be green, pink, red, yellow, blue.

[00:31:40]So no blue here because of anti- knight and anti- king or in normal sudoku.

[00:31:47]No red yellow here because of red. Red has to be one of these two which sees that cell. Pink has to be one of these three which sees this cell. So this can't be pink. Yellow sees that cell by normal sudoku. So this is green which eliminates green in the rest of the row.

[00:32:08]This can't be yellow because of anti- night.

[00:32:14]Um, so it's red or pink or red.

[00:32:18]Uh, this can't be pink because of anti-ight.

[00:32:29]This can't be yellow because of anti-night. So, where is yellow? It's one of these two. Okay.

[00:32:40]Um remaining colors of row eight we have light, medium, no dark, no green, no pink, no orange, it's red and yellow.

[00:32:52]Okay. Um no red here because of anti Oh, this can't be red because of anti- king.

[00:32:58]So that's pink, which eliminates pink in the rest of the row.

[00:33:02]Pink here eliminates pink here because of anti- king and anti- knight. So this is a medium light pair which eliminates medium and light in the rest of the box or row and box. So this can't be light.

[00:33:16]That's red. This can't be red. It's pink. That eliminates pink here. Red eliminates red here. So this is light.

[00:33:27]Red eliminates red here. So that's blue.

[00:33:29]Which eliminates blue and the rest of the row. This is a yellow red pair which eliminates yellow and red in the same box. This is light and medium which eliminates light and medium in the same row. So this is yellow. This can't be yellow here. It's red.

[00:33:45]Okay.

[00:33:51]Um I don't know remaining colors in this lower left hand box we have light, medium and orange.

[00:34:11]Okay, this can't be orange because of orange in the column.

[00:34:17]Orange is here.

[00:34:20]So if we try to have so for every third cell on this entropic line because every three cells has to contain one of each set. These are all different sets and orange must be the same set as dark. So therefore, orange cannot be here because it's the same set and they would not have three of the same entropic. Um, we would not have one of each set of the entropic sets if this was orange. So this cannot be orange, which means this is orange. Here we have a medium light pair in column 2, which means the remaining colors are orange and blue.

[00:35:01]Orange can't be here because of orange row. So that's blue, which makes this orange. Remaining colors in row nine are blue, green, and pink. And this cannot be green or pink because of anti- king and anti- knight.

[00:35:18]So that's blue. This can't be pink because of anti- knight. So that's green, which makes this pink there.

[00:35:26]Uh medium here means this can't be medium. This is light, which means this can't be light. That's medium.

[00:35:33]This last color here is blue, yellow or orange or blue, yellow or red.

[00:35:41]Okay.

[00:35:49]Um, we have light remaining in column 7.

[00:35:54]Cannot be here because of anti-ignite.

[00:35:56]Can't be here because of light of medium in the row. So, this is medium there.

[00:36:02]Which means medium has to be one of these two cells in row three. Cannot be here because of anti- night. So it must be here. Which means this can't be medium. That's light. This can't be light. That's medium. Which means this can't be medium. That's light. Which means this can't be light. That's medium.

[00:36:20]Okay. And then let's fill out the rest of the colors. In column one. We have pink and yellow. This can't be pink because of anti- night. So this is yellow which makes this pink.

[00:36:34]Column three we have light green and red. This can't be light or green because of anti- king and anti- knight.

[00:36:44]So that's red. This can't be light because of anti- knight. So this is green which makes this light here. Red eliminates red here. So that's green.

[00:36:55]This can't be green then anymore. And this can't be light because of light in the row.

[00:37:01]So that's a red which eliminates red here. So that's light.

[00:37:05]Red eliminates red here. So this is blue or yellow.

[00:37:10]Remaining color in row two is a red.

[00:37:15]Remaining that red eliminates red here.

[00:37:17]So this is yellow which eliminates yellow here. So that's red. So these both can't be red which means that leaves this as a red.

[00:37:26]Okay. Remaining colors of row one have to be blue, yellow, and green. Green can't be here because of anti-night.

[00:37:39]Can't be blue here because of of blue in the column. So this is yellow which eliminates yellow here. So it's blue which eliminates blue here. So it's yellow which forces that to be blue and therefore this is green.

[00:37:52]Um, and we are left with pink and light. This can't be light because of anti- kingings. So, this is pink, which makes this light here.

[00:38:04]Okay. So, now we have everything set up.

[00:38:14]We know blue and dark are one or four adding up to Sorry, blue or is it dark?

[00:38:21]Yeah, blue and dark are one and four or two and three and blue and dark are necessarily part of different entropy sets.

[00:38:33]So therefore, blue and dark have to be one and four, but we don't know which one's which.

[00:38:47]Um, blue is the same entropic set as medium.

[00:38:55]So, blue dark. Wait, hold up.

[00:38:59]Yeah, they're different entropic sets.

[00:39:04]Okay, so these have to be one and four.

[00:39:11]Um, which means [snorts] These 10ens cannot add up to 1 9 or 46 because they don't contain blue or dark in them. [snorts] So that means pink yellow and light medium have to be a pair of 28 and 37.

[00:39:43]Um well obviously yellow is in a 1:2 ratio with that so cannot be seven and two can only be in a 1:2 ratio with one or four which is blue or dark.

[00:40:03]So this can't be three. Therefore this can't be two. This can't be eight. So this is necessarily three or eight. And three, eight can only be in a 1:2 ratio with four, which orange cannot be. So yellow has to be three.

[00:40:19]So yellow's three, pink is seven, orange is six.

[00:40:27]So green must be high. So it's eight or nine. And it cannot be eight because this is a two uh this is a 27 28 pair here to add up to 10. So green must be nine.

[00:40:43]Uh medium then has to be a middle pair.

[00:40:46]So mediums are four which means blues have to be low and they are one.

[00:40:53]Um that means uh medium is two, light is eight and red is five.

[00:41:06]And that's the solve. Um, I would not classify this as very easy. The execution on this is is not the logic is very easy, but the execution I would say on this is kind of is at is probably average.

[00:41:23]Um, but that's also because I'm very bad at anti night rules because I just don't see them. I mean, I've I've gone through I've done a lot of anti- night puzzles and I just don't see them very well. I I either mischaracterize something or I miss something and it's just not good.

[00:41:45][laughter] I'm just not good at them. I I don't know what to tell you. So, maybe just for me, this is not very easy. But maybe if you spot anti-ight moves pretty well, then it should be very easy for you. I don't know.

[00:42:02]Anyways, I hope you enjoyed this episode of Learn How to Sudoku and I'll see you next time on Frank Puzzles. Take care.