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Time for a real toughie to celebarate another milestone. 30 Assassins here! This one has an SS(v3.2.1)score of 1.48. I used some short chains to solve it - the sort of chains I really like: single digit, strong-weak links. Just variations on Grouped X-wing really. Fun! I'll give it a rating of Hard 1.50. I was thinking of going a touch higher, but then found a "45" I'd missed the first time through. [edit: not "found". Made a mistake. Not a disaster this time though. But will push up my estimated rating a fraction to what I first thought. Good luck!]

Note that this puzzle has 4 zig-zag cages but...none of them cross.

I've put the solver log below in case you want a hint. If this is too hard, please try the Messy Ones #4-6! A reminder that we need a volunteer for A131.

Assassin 130 (NOTE: 1-9 cannot repeat on the diagonals)



Cheers
Ed

Oh, my! That looks outta my league, Ed! I'm headed over to the Messy Ones, but will be back to look at walk-thrus and comments!

Nice Killer, Ed! This one offered lots of fishy moves though I tried to avoid them as best as I could.

A130 Walkthrough:

1. R123
a) Innies N2 = 16(2) = {79} locked for R3+N2
b) Innies R1 = 3(2) = {12} locked for R1
c) 14(3) = {356} locked for R1+N2
d) 13(2) = {49} locked for R1+N1
e) 15(2) = {78} locked for N3
f) 3(2) = {12} locked for C7+N3
g) Naked quad (1248) locked in R2C4567 for R2
h) 9(2) = {27} -> R1C3 = 2, R2C3 = 7
i) R1C7 = 1, R2C7 = 2
j) 15(4) = {1248} -> R3C5 = 2
k) 12(3) = {156} because R2C12 = (356) -> R3C1 = 1; {56} locked for R2+N1

2. R1234
a) 18(3) = {369} because R2C89 = (39) -> R3C9 = 6; 3 locked for N3
b) 33(5) = {45789} because R3C78 = (45) -> 8 locked for R4; R4C68 = (789)
c) 32(5) = {35789} because R3C23 = (38) -> 5 locked for R4; R4C24 = (579); CPE: R2C2 <> 5
d) R4C7 = 3, R2C2 = 6, R2C1 = 5
e) Naked quad (5789) locked in R4C2468 for R4
f) 11(4) = {1235} -> 5 locked for R5; CPE: R5C9 <> 1,2

3. R6789
a) 13(4) = 1{237/246/345} -> 1 locked for C2+N7
b) Outies R89 = 9(2): R7C6 <> 1,9
c) 19(5): R67C9+R7C8 <> 8,9 because R67C7 >= 9
d) R6C3 <> 8,9 since it sees all 8,9 of N7
e) R7C2 <> 5 since it see all 5 of N4

4. R145 !
a) ! Generalized X-Wing: 8 locked in R14 (R1C89+R4C68) for C8+D/
b) R5C4 <> 4,6 since it sees all 4,6 of R4

5. N69!
a) ! Hidden Killer triple (123) in R7C89 + 23(4) for N9 since 23(4) can only have one of (123)
-> 23(4) must have one of (123); R7C89 = (123)
b) R7C7 <> 5 since it sees all 5 of C9
c) 19(5): R6C7 <> 8 because R7C7 <> 1,2,3,5
d) 19(5) <> 8 because R6C79 = 5[1/2] blocked by R4C9+R5C8 = (125)

6. N6 !
a) 19(5) = 1{2349/2367/2457/3456} -> Either R6C9 = (12) xor R6C79 has 5 since
3 only possible @ R7C89 and 5 only possible @ R6C79
b) ! Killer triple (125) locked in R4C9+R5C8+R6C79 for N6
c) 20(4) must have one of (123) -> R6C6 = (123)
d) 20(4) = 4{169/178/268/367} because (123) only possible @ R6C6 -> 4 locked for N6
e) 19(5): R7C7 <> 9 since 4 only possible there

7. C37 + D\ !
a) ! Finned X-Wing for 8 in C37 for R59 with fins R3C3+R8C7:
Either X-Wing in C37 locked for R59 or one of R3C3,R8C7 has 8 -> CPE: R9C9 <> 8
b) Hidden Single: R3C3 = 8 @ D\
c) R3C2 = 3
d) ! Hidden Killer triple (123) in R5C5+R6C6+23(4) for D\ since 23(4) can only have one of (123)
-> R5C5 = (13); R8C9+R9C8 <> 1,2,3
e) 21(4): R67C5 <> 1,3 because R45C5 <= 9 and R4C5 <= 6

8. R4567 + D\
a) 8 locked in R7C12 @ N7 for R7+28(5)
b) Outies R89 = 9(2) <> 1
c) 1 locked in R7C89 @ R7 for N9+19(5)
d) 1 locked in R5C5+R6C6 @ D\ for N5
e) 21(4): R6C5 <> 4,6 because 8 only possible there
f) Hidden pair (46) in R4C5+R6C4 for N5 -> R6C4 = (46)

9. N47 + D/
a) 2 in D/ locked in R8C2+R9C1 for N7
-> 13(4) = 12{37/46}
b) 5 locked in R789C3 @ N7 for C3
c) 25(4) <> 1 because R6C4 = (46)
d) 25(4) = 6{289/379/478} <> 5 because R6C4 = (46) and R4C2 = (579) blocks {4579}
- R5C1 <> 4,6 since R5C3 <> 7,8
-> CPE: R6C13+R7C3 <> 6
e) Hidden Single: R4C2 = 5 @ N4

10. D\ + C789
a) Naked triple (479) locked in R1C1+R4C4+R7C7 for D\
b) 5 locked in R8C8+R9C9 @ D\ for N9
c) 23(4) = 5{279/369/378} <> 4
d) Hidden Single: R5C9 = 4 @ C9, R3C8 = 4 @ C8
e) R3C7 = 5
f) 19(5): R6C9 <> 7 because 5 only possible there
g) Hidden pair (78) in R18C9 for C9 -> R8C9 <> 9
h) Hidden Single: R2C9 = 9 @ C9
i) R2C8 = 3, R5C5 = 1

11. N69 + D/
a) 20(4) = 46{28/37} -> 6 locked for N6
b) 19(5) = 124{39/57} -> R7C7 = 4; CPE: R9C9 <> 2
c) R1C1 = 9, R1C2 = 4, R7C3 = 9
d) Naked pair (78) locked in R1C9+R4C6 for D/
e) R8C2 = 2, R8C8 = 5, R9C9 = 3
f) 23(4) = {3578} -> R9C8 = 7, R8C9 = 8
g) 19(5) = {12457} -> R6C7 = 7, R6C9 = 5; 2 locked for R7

12. N8
a) Outies R89 = 9(2) = {36} locked for R7+N8
b) 18(3) = {369} -> R8C6 = 9, R8C7 = 6, R7C6 = 3

13. Rest is singles without considering diagonals.

Rating: 1.5 - (Hard) 1.5. I used a Finned X-Wing and some Killer triples.

I've written a nice complete walkthrough for this one (been a while since I have the time/energy to do that).

Note I didn't use any fish at all, although some ????????-?????? people might consider my critical moves "chainy".


This is one of those puzzles where you can focus on one single weak spot then crush and crush until it breaks open. Although I listed 3 critical steps here, they actually feel like one single big step at one single spot. I regard this as "trinity" (3 as 1, 1 as 3).

Long live self-censorship!

_________________
ADYFNC HJPLI BVSM GgK Oa m

Udosuk: thanks for the "although" warning. I like to have some warning rather than getting a shock.

However, the extra put-down adjectives you use to describe people like me hurts. So, I won't be reading your WT. Thin-skinned at the moment. Love udosuk's edit in tiny-text his previous post! Whole-heartedly agree!!

Cheers
Ed

I probably will use that "put-down adjective" to describe myself, but sorry if it offended you (or other people) that much.

You probably won't hear from me for quite a while, so let me just give you all an early Christmas greeting now!

_________________
ADYFNC HJPLI BVSM GgK Oa m

Another one that I struggled with. Thanks Ed for making me work so hard! I finished while it was still an active puzzle but I've only just gone through the walkthroughs posted by Afmob and udosuk.

I'll rate A130 as 1.75 the way I solved it but that's clearly too high. After going through the other two walkthroughs, Hard 1.5 looks right for it.

If you go through my walkthrough, you will see that I missed something in step 9. I could have added "5 locked for R4" at the end of step 9b and if I had I might have spotted step 30 then. However I think I'd already spotted the naked quad in step 9c and then forgot about those locked 5s. Afmob, udosuk and Ed, plus anyone else who spotted that CPE easily, probably never realised that fixing R2C2 as 6 is one of the key things in solving this puzzle. Anyway if I'd spotted that CPE in step 9 this walkthrough would never have been posted.

Here is my walkthrough. As usual I've given eliminations on the diagonals to make it easier for those of us who do our eliminations manually.

Prelims

a) R1C89 = {69/78}
b) R1C12 = {49/58} (cannot be {67} which clashes with R1C89)
c) R12C3 = {18/27/36/45}, no 9
d) R12C7 = {12}, locked for C7 and N3
e) 10(3) cage at R7C4 = {127/136/145/235}, no 8,9
f) 11(4) zig-zag cage at R4C7 = {1235}, CPE no 1,2,3,5 in R5C79
g) 13(4) cage in N7 = {1237/1246/1345}, no 8,9, 1 locked for N7
h) 32(5) cage at R3C2 = {26789/35789/45689}, no 1
i) 33(5) cage at R3C6 = {36789/45789}, no 1,2

1. 45 rule on R1 2 innies R1C37 = 3 = {12}, locked for R1, R2C3 = {78}
1a. 3 in R1 locked in R1C456, locked for N2

2. Killer pair 8,9 in R1C12 and R1C89, locked for R1

3. Grouped X-Wings for 8,9 in 32(5) cage at R3C2 and 33(5) cage at R3C6, no other 8,9 in R34

4. 45 rule on N2 2 innies R3C46 = 16 = {79}, locked for R3 and N2

5. R1C456 = {356} (only remaining combination), locked for R1 and N2, clean-up: no 8 in R1C12, no 9 in R1C89

6. Naked pair {49} in R1C12, locked for N1
6a. Naked pair {78} in R1C89, locked for N3

7. 8 in N2 locked in R2C456, locked for R2 -> R2C3 = 7, R1C3 = 2, R12C7 = [12]

8. 33(5) cage at R3C6 = {36789/45789}
8a. Hidden triple {789} R3C6 + R4C68 for 33(5) cage -> R4C68 = {789}, 8 locked for R4
8b. R3C78 = {36/45}

9. 45 rule on N1 2 innies R3C23 = 11 = {38} (cannot be {56} which clashes with R3C78), locked for R3, N1 and 32(5) cage at R3C2, clean-up: no 6 in R3C78 (step 8b)
9a. Naked pair {45} in R3C78, locked for N3 -> R3C9 = 6, R3C1 = 1, R3C5 = 2
9b. R3C23 = {38} -> 32(5) cage at R3C2 = {35789}, R4C24 = {579}
9c. Naked quad {5789} in R4C2468, locked for R4 -> R4C7 = 3
[At this stage I missed something fairly easy, see step 30]
9d. 5 in 11(4) zig-zag cage at R4C7 locked in R5C68, locked for R5
9e. 1 in N7 locked in R89C2, locked for C2

10. 45 rule on R89 2 outies R7C46 = 9 = [18]/{27/36/45}, no 1,9 in R7C6

11. 19(5) cage at R6C7 = {12349/12358/12367/12457/13456}
11a. R6C9 + R7C89 = {123/124/125/134/135} (because R67C7 cannot be {45} which clashes with R3C7), no 6,7,8,9, CPE no 1 in R89C9

12. 10(3) cage at R7C4 = {136/145/235} (cannot be {127} because R8C3 only contains 3,4,5,6), no 7, clean-up: no 2 in R7C6 (step 10)

13. 45 rule on N6 3 innies R4C8 + R6C79 = 2 outies R56C6 + 14
13a. Max R4C8 + R6C79 = 22 -> max R56C6 = 8, no 8,9 in R6C6
13b. 4,6 in N6 locked in R5C79 + R6C789, CPE no 4,6 in R6C6

14. Hidden killer triple in R7C89 and 23(4) cage for N9, 23(4) cage cannot have more than one of 1,2,3 -> R7C89 = {123}, 23(4) cage must contain one of 1,2,3
14a. 23(4) cage in N9 = {1589/1679/2489/2579/2678/3479/3569/3578} -> R789C7 = {467/468/469/478/567/568} (cannot be {458/459} which clash with R3C7, cannot be {569} which clashes with 23(4) cage)
14b. 23(4) cage = {1589/2489/2579/3479/3569/3578} (cannot be {1679/2678} which clash with R789C7)
14c. Killer pair 4,5 in R3C7 and R789C7, locked for C7

15. 19(5) cage at R6C7 (step 11) = {12349/12358/12367/12457/13456}
15a. 8,9 of {12349/12358} must be in R6C7 -> no 8,9 in R7C7

16. Hidden killer quad 6,7,8,9 in R4C8, R56C7 and R5C9 + R6C8 for N6 -> R5C9 + R6C8 must contain one of 6,7,8,9
16a. Min R5C79 + R6C8 = 14 -> no 7 in R6C6

17. 19(5) cage at R6C7 (step 11) = {12349/12358/12367/12457/13456}
17a. 3 of {12349/12358/12367/13456} must be in R7C89
17b. {12457} must have R7C7 = {45}, R7C89 = {12} => R7C46 = {36} (cannot be {45} which clashes with R7C7)
17c. -> 3 locked in R7C46 + R7C89, locked for R7

18. 8,9 in N7 locked in R7C123 + R9C3, CPE no 8,9 in R6C3

19. 23(4) cage in N9 (step 14a) = {1589/2489/2579/3479/3569/3578}
19a. R2C89 and 23(4) cage = {1589/2489/2579/3479/3569} form X-Wing in 9 for C89
19b. R1C89 and 23(4) cage = {3578} form X-Wing in 7,8 for C89 => R4C8 = 9
19c. -> no 9 in R5C9 + R6C8

20. 23(4) cage in N9 (step 14a) = {1589/2489/2579/3479/3569/3578}
20a. 23(4) cage = {1589/2489/2579/3479/3578} plus R1C89, R2C89 and R4C8 contain all of 7,8,9 for C89, locked for C89
20b. R2C89 and 23(4) cage = {3569} form X-Wing in 9 for C89 => naked pair {78} in R14C8, locked for C8
20c. -> no 7,8 in R6C8

21. 23(4) cage in N9 (step 14a) cannot be {3569}, here’s how
23(4) cage = {3569} => R789C7 = {478} clashes with 19(5) cage at R6C7 = {12457} (all other combinations for the 19(5) cage have 3 in R7C89)
21a. -> 23(4) cage in N9 (step 14a) = {1589/2489/2579/3479/3578}, no 6

22. R6C8 = 6 (hidden single in C8)
22a. Naked triple {789} in R4C8 + R56C7, locked for N6 -> R5C9 = 4
22b. R5C9 + R6C8 = 10 -> R5C7 + R6C6 = [71/82/93], no 5 in R6C6

23. 19(5) cage at R6C7 (step 11) = {12349/12358/12367/12457} (cannot be {13456} because R6C7 only contains 7,8,9), CPE no 2 in R89C9
23a. 3 of {12349/12358/12367} must be in R7C9 (R67C9 cannot be {12} which clashes with R4C9), no 3 in R7C8
23b. 7 of {12367/12457} must be in R6C7 -> no 7 in R7C7

24. 2 on D\ locked in R6C6 + R8C8, CPE no 2 in R8C6

25. 5 in C9 locked in R6C9 + R89C9
25a. 5 in R6C9 can only be in 19(5) cage at R6C7 = {12457} => R7C7 = 4 => R3C7 = 5 => no 5 in R789C7
25b. 5 in R89C9 => no 5 in R789C7
25c. -> no 5 in R789C7, clean-up: no 8 in R6C7 (step 23)

26. R3C7 = 5 (hidden single in C7), locked for D/, R3C8 = 4
26a. 4 on D\ locked in R1C1 + R7C7, CPE no 4 in R7C1

27. 5 in N9 locked in 23(4) cage (step 21a) = {1589/2579/3578}
27a. 5 of {1589/2579} must be in R89C9 (R89C8 cannot be {15/25} which clash with R57C8) => they must have one of 7,8,9 in C8 and one in C9 => killer triple {789} in R1C8, R4C8 and R89C8, locked for C8
27b. {3578} must have one of 7,8 in C8 and one in C9 (otherwise clashes with R1C89) => killer triple {789} in R1C8, R4C8 and R89C8, locked for C8
27c. -> Killer triple {789} in R1C8, R4C8 and R89C8, locked for C8 -> R2C8 = 3, locked for D/, R2C9 = 9

28. 18(3) cage at R7C6 = {369/378/459/468/567} (cannot be {189} because R78C6 = [81] clashes with R7C46 = [18]), no 1
28a. 9 of {369/459} must be in R8C6 (R78C6 cannot be {36/45} which clashes with R7C46 = {36/45}), no 9 in R8C7
[With hindsight step 28a could have been done after step 10; R78C6 cannot total 9 because of the overlap with R7C46.]

29. 18(4) zig-zag cage at R4C1 = {1269/1368/1467/2349/2367} (cannot be {1278} because R4C13 = [21] clashes with R4C9)
29a. Hidden killer triple 7,8,9 in R5C135, R5C24 and R5C7 for R5 -> R5C135 must contain one of 7,8,9
29b. 25(4) zig-zag cage at R5C1 = {1789/2689/3589/3679/4579/4678}
29c. 1 of {1789} must be in R5C3 (because R5C135 only contains one of 7,8,9) -> no 1 in R6C4
29d. 1 on D/ locked in R5C5 + R8C2, CPE no 1 in R8C5

30. 5 in R4 locked in R4C24, CPE no 5 in R2C2 using D\
30a. R2C2 = 6, locked for D\, R2C1 = 5, R7C7 = 4, locked for D\, R1C1 = 9, locked for D\, R1C2 = 4, clean-up: no 5 in R7C46 (step 10)
30b. Killer triple 1,2,3 in R7C46 and R7C89, locked for R7

31. 6 on D/ locked in R7C3 + R9C1, locked for N7
31a. 13(4) cage in N7 = {1237/1246} (cannot be {1345} which clashes with R8C3), no 5
31b. 6 of {1246} must be in R9C1, no 4 in R9C1

32. 23(4) cage in N9 (step 27) = {1589/2579/3578}
32a. 9 of {1589/2579} must be in R9C8 -> no 1,2 in R9C8

33. 4 in R9 locked in R9C3456, locked for 35(6) cage at R8C5, no 4 in R8C5

34. 18(3) cage at R7C6 (step 28) = {369/378/459/468/567}
34a. 4,5,9 of {369/468/567} must be in R8C6 -> no 6 in R8C6

35. Hidden killer pair 1,2 in 10(3) cage at R7C4 and 35(6) cage at R8C5 for N8 -> 35(6) cage at R8C5 must contain one of 1,2
35a. 35(6) cage at R8C5 = {146789/245789}, no 3

36. R6C4 = 4(hidden single on D/)
36a. 25(4) zig-zag cage at R5C1 (step 29b) = {4579/4678}, no 1,2,3, 7 locked for N4
36b. 5 of {4579} must be in R6C2 -> no 9 in R6C2

37. 2 on D/ locked in R8C2 + R9C1, locked for N7

38. 4 in R4 locked in 18(4) zig-zag cage at R4C1 (step 29) = {2349} (only remaining combination, cannot be {1467} because R5C2 only contains 2,3,8,9) -> R4C13 = [24], R4C9 = 1, R4C5 = 6, R5C24 = {39}, locked for R5

39. R5C5 = 1 (hidden single in R5), locked for D/ and D\
39a. R6C3 = 1 (hidden single in R6)
39b. R89C2 = [21] (hidden singles in C2, 2 also hidden single on D/)
39c. R6C6 = 2 (hidden single on D\), R5C68 = [52], R6C9 = 5
39d. R2C6 = 1 (hidden single in C6), R2C45 = [84]
39e. R8C1 = 4 (hidden single in C1), R9C1 = 6 (step 31a)
39f. R6C1 = 3 (hidden single in C1), R5C24 = [93], R4C4 = 7, locked for D\, R4C2 = 5, R3C4 = 9, R3C6 = 7, clean-up: no 2 in R7C4, no 6 in R7C6 (both step 10)

40. Naked pair {78} in R7C12, locked for R7 and N7 -> R7C3 = 9, locked for D/, R89C3 = [35], R3C3 = 8, locked for D\, R4C6 = 8, locked for D/

and the rest is naked singles