Sudoku that’s not Completely Sneaky

Lilliputian Arrows by 99% Sneaky:
Normal sudoku rules apply. Digits along an arrow sum to the digit in the attached circle. Cages show their sums.

We think that, once you have solved hand-crafted sudoku puzzles, you will not be satisfied with machine-generated puzzles ever again! All our apps are full of handmade sudoku puzzles by ourselves and many of the best constructors in the world, tested and hinted by Simon and Mark! Links are ALL here: or search for Cracking the Cryptic and the app name on your favourite app provider: Classic, Killer, Chess, Miracle, Thermo, Arrow, Sandwich, Domino and GAS. (Coming soon: a Lines Sudoku pack!)

▶ Our main app ◀
Our main Cracking the Cryptic app features several puzzle packs, including GAS 1 and 2, Domino Sudoku, and coming soon a pack based on Line Sudoku! Also in that app: a free pack of puzzles by Prasanna Seshadri (one puzzle of each variant of our other apps), and a FREE pack of 23 puzzles in celebration of our reaching 500k subscribers.


The deadline to submit your answer to our August Patreon Reward sudoku hunt, “Tennis Anyone,” passed as of the 20th of the month. The content is still available (along with past Patreon Rewards and many other things), and there will be a brand new reward released on the first of September! Join us at the $2/month level or higher for the monthly reward, $3/month or higher to have access to solution videos. (Any member has access to a Patreon-only discord channel to discuss the puzzles and get help!)

▶Our merchandise: ◀

▶Miss the Kickstarter? You can still preorder our book here ◀

▶ SUDOKU PAD ◀ Input classic sudoku puzzles into our software. With 12 free puzzles:
Amazon: Search for “SudokuPad”



[email protected]
Snailmail: Mark Goodliffe, Box 102, 56 Gloucester Road, London SW7 4UB

Twitter: #crypticcracking
Instagram @crackingthecryptic

Music: Tim McCaskey (Guitar) or Lucy Audrin (Piano): Mozart’s Sonata no 16; and Mark’s outro music by Riffclown.
SOFTWARE: Thanks to Sam Cappleman-Lynes and Sven Neumann
Logo: Melvyn Mainini
Opening Credits: Joel Blundell

Hi! We’re Simon Anthony and Mark Goodliffe, two of the UK’s most enthusiastic puzzle solvers. We have both represented the UK at the World Sudoku Championships and the World Puzzle Championships. We’re also “cryptic crossword” aficionados. Mark is the twelve-time winner of The Times championship and Simon is the former record holder for most consecutive correct solutions to The Listener crossword. We hope we can help your puzzle solving while also introducing you to some of the world’s best puzzles.

Thank you for watching!
Simon and Mark
▶ Contents ◀
0:00 Theme Music & News around the channel
2:58 Rules of today’s puzzle
3:30 Start Of Solve – Let’s Get Cracking!


  1. 39.05 hard to find the break in, smooth after that. Finished on a 3 in the corner.

  2. 12:47
    Very elegant opening. Noted the 9 cages match with 4 arrow cells in their region and 6 cells of different digits must be at least 21. Subtracting the 9 meant the arrow pair was at least 12, for a slight variation on the opening break in, though it's essentially yhe same logic.

  3. Looks to be a little more approachable compared to the 1 Simon did.

  4. 52:47 – a lot longer than most of you, but I'm proud of myself as this was slightly more difficult than the ones I usually limit myself to. Beautiful puzzle, very enjoyable to solve it!

  5. 20:41 for my time (conflict checker off) with a little nudge from the start of Mark's solve. Very fun puzzle, props to 99% Sneaky!

  6. Roping in the bottom 3 rows helped the 2nd step of this solve a lot for me. Took me a long time to figure out which circle in B5 was the 6, but I had already figured out if it was in r6c6 the bottom 3 rows were very set.

  7. 36:46 with a peak to see how to figure out the 6 in Box 5. Neat break in I couldn't figure out.

  8. Who wants a sudoku?
    (Speaking of the merch at 2:18)
    It used to be on a hoodie or shirt in the merch about 5 years ago.

    Anti-knight's move, anti-king's move, and non-consecutive orthogonally .
    Apparently, Mark said "It's solvable," with the given digits (only four) but do yourself a favor and stick a 3 in r6c6 (it solves "Miracle-like").

    1 (in 3c3)
    2 (in r3c5)
    [That "3" in r6c6]
    2 in r7c9
    And a 5 in r9c9

    That's it.
    (Even use this grid if ya want – just ignore the cages and such).

    There it is though.

  9. The link to play this puzzles in Sven’s SudokuPad app is broken. Like 60% of CtC’s links to play the puzzle in the iOS app are broken lately.

  10. I don't understand how I can get the other of today's puzzle without much trouble, but this one I can't figure out how to get past the 6789 deduction in box 5, and then 45 minutes end up with a conflict (and not even half the digits done)

  11. Ok im officially stuck. 45mins of trying things and i cant find the break in . Time to watch and feel stupid.

  12. 14:30 With the 6 issue from the video, I managed to solve the puzzle. Just now, Mark omitted a possible 2 in R2C4, which is going to bite him if he doesn't eventually correct it. He probably will.
    21:20 Ahah. He found it.

    Is this puzzle really sneaker than many puzzles here?

  13. @9:47
    That puts 36 into the nine cage.

    And with "789" in there (and 6789 in the "15 cage" in box7), notice where the 6s are in that quadruple.
    [In the 15 cage]

    That makes that cage a 69.
    That's never happened before.
    [Which of course, leaves a 78 pair and the 9 in the circle in box8]

    That "9" is then on the left in box5 (and placeable in box2 above).

    Then you can place the 9 in box9, and placed in box3 and placed in box1 (leaving an x-wing on 9s in boxes4&6).

    Very nice.

  14. 35:34 for me. I feel like the setters are intentionally putting 3s in corners.

  15. I hope I don't come off as freaky
    Or, heaven forbid, much too geeky.
    But whenever I eye
    "Normal rules still apply"
    Well, it just doesn't seem very sneaky.

  16. Omg I’m so glad you finally added the 2 around 21:30 or so to r2c4! I was wondering why it was left out earlier 😅

  17. I may have been unkind last time by saying 99% obvious (rather than sneaky)… This time I'll stand by it. Completed in 6m41s.

  18. Mark used to be such a good solver but now he just stooped to Simon's level. Such bad scanning and jumping erratically all over the grid. And the man is thinking of going to Sudoku World Championship! I sincerely hope you do well, Mark – just like last year in Kraków – but unless you raise your solving back to the level it was before you'll need a lot of luck.

  19. Good sudoku, did it in 18 min 18 sec, which means again I’m quicker than Mark, party time 🥳 🎉

  20. Solved in 23:06 but I didn't get the break-in, I guessed something trying to prove it wrong but it wasn't, so I finished the puzzle.

  21. Are my eyes failing, or are Mark's videos getting fuzzier and fuzzier by the day? The corner marks are darkish grey smudges on a slightly paler grey background – especially towards the bottom right.

  22. That was very clever. I could not see the break in, but having watched Mark show why neither cell 3 nor 7 in box 5 could be the 6 it all fell into place beautifully.

  23. Took me forever to find this break-in! Impressively efficient solve from Mark.

  24. anyone else doesnt see the arrows? its all white when i do the puzzle. i have to grey every tile to see whats going on there

  25. Amazing how long I can sometimes stare at a puzzle and not spot something that would massively help me solve it (the 6 in box 5). It made me feel very small, but I take full responsibility. No reflection on the setter to whom I apologise for not spotting his very neat trick for so long.

  26. 42:08. Forgot that trick. Made solving extremely difficult, but survived. Lol

  27. Spotted the 9 thing immediately… took me a lot longer to spot the 6 issue in r3 & resolve the 6s rotationally and resolve box 5.

  28. Did Magoo forget about the secret when doing box 3? Once the 8 was known in the arrow, 8 times 3 plus the 10 killer cage makes 34, take that from the secret (45 shh don't tell anyone) leaves 11. We know 9 is in there from sudoku of all things, and yes you should do sudoku in a sudoku puzzle (don't listen to Simon , regardless of how interesting he is at parties), so we know it's 9&2 in the other cells.

  29. This puzzle looks like the CTC hat. lol

  30. I'm confused in R3 6 digits must be at least 21. Subtract 6 and you get 15. Where is mark getting 18 from?

  31. That wasn't difficult but it was really cleverly built. A very enjoyable puzzle to solve. Thanks for sharing it.

  32. Mark is almost channeling Simon here with the refusal to do Sudoku

  33. 57:04 for me in this one. This had several bits I found quite tricky, including the break-in which I only got with Mark's help in the video.

  34. There has been a string of puzzles recently with straightforward variant rules, in good combinations, that have produced really excellent and fun puzzles – and all within my ability to solve. Not just GAS, but something a bit more than GAS. I really enjoyed this puzzle and your solve of it, Mark. Your ability to spot patterns is very fun (such as the portions that you colored green). But even beyond that, your reasoning was so clear and so great throughout. Thanks for this video!

  35. Took me ages to spot the start, tried lots of ways to whittle the options down, tried SET, no joy. Came back to it fresh and saw it straight away.

  36. After working on box 8 (13:00), major results can be obtained by using basic sudoku.

  37. What I noticed happens in box 3. Sudoku puts a nine in R1C8 or 9. Together with "the secret" we get: the 8 and its two arrows add up to 24, a 10 cage makes the total 34. That leaves exactly 11 for R1C89. So the other digit must be 2. That rules out 26 as a way to make up 8, 53 doesn't go vertical, so it goes horizontal leaving 17 for the vertical arrow and 64 for the cage.

    Oh and to get the 8 in box3 the easy way of seeing it is that the 8 in R9C9 puts an 8 in C8 in box 6. Therefore there must be an 8 in C7 in box3. Now that could be on the arrow with a 1 putting a 9 in the circle. But that's not the case because of the R3C3 nine. So the 8 is in the circle.

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