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After the last couple of Assassins were quite hard for V1 standards, I decided to give you an easy Killer to help you relax. But if you really want a tougher version then you should volunteer for A177, so that udosuk can post his A175 V2 or I might make a V2.

Assassin 176


Note: No repeat on the diagonals! (Not required for uniqueness)

3x3:d:k:5377:3850:3850:3850:3854:3854:5140:5140:3602:2051:5377:5644:5644:3854:3600:5140:3602:5143:2566:2051:5377:5644:3600:3600:3602:5143:5143:4615:2566:3848:5377:5377:3602:7193:7193:5143:4615:3848:3593:3593:3593:7193:2584:2584:2584:4615:2821:3848:7426:7426:5139:7193:7193:4886:2821:2564:7426:4365:2833:2833:5139:4886:4886:2564:7426:4365:4365:4623:2833:3861:5139:4886:7426:2827:2827:2827:4623:4623:3861:3861:5139:


Estimated rating: 1.0.
SS Score: 1.00 (Coincidence?)

Thanks Afmob for an easier Assassin. It's good that you have time to create and post Assassins again.

Manu has now volunteered for A177 so you can now post a v2 if you want. You wrote "Note: No repeat on the diagonals! (Not required for uniqueness)". Maybe A176 without the diagonal restraint would make a good v2? I don't know how hard it would be but it looks a lot harder because it takes away my breakthrough steps 8 and 9. Udosuk was, of course, already allowed to post the harder variants of A175 although it would probably be a good idea to wait until some walkthroughs have been posted for "v0.25", "v0.5" and "v0.75".


Here is my walkthrough.

Prelims

a) 8(2) cage in N1 = {17/26/35}, no 4,8,9
b) 10(2) cage at R3C1 = {19/28/37/46}, no 5
c) 11(2) cage at R6C2 = {29/38/47/56}, no 1
d) 10(2) cage in N7 = {19/28/37/46}, no 5
e) 22(3) cage at R2C6 = {589/679}, CPE no 9 in R2C56
f) 20(3) cage in N3 = {389/479/569/578}, no 1,2
g) 10(3) cage in N6 = {127/136/145/235}, no 8,9
h) 11(3) cage at R7C5 = {128/137/146/236/245}, no 9
i) 11(3) cage at R9C2 = {128/137/146/236/245}, no 9
j) 14(4) cage at R1C9 = {1238/1247/1256/1346/2345}, no 9

1. 45 rule on R5 3 innies R5C126 = 21 = {489/579/678}, no 1,2,3

2. 45 rule on C1234 3 outies R456C5 = 21 = {489/579/678}, no 1,2,3

3. 45 rule on C789 3 outies R456C6 = 11 = {128/137/146/236/245}, no 9
3a. 7,8 of {128/137} must be in R5C6 -> no 7,8 in R46C6

4. 45 rule on N3 2 outies R4C69 = 9 = [18/27]/{36/45}, no 9, no 1,2 in R4C9

5. 45 rule on N9 2 outies R6C69 = 9 = [18/27]/{36/45}, no 9, no 1,2 in R6C9

6. 45 rule on N2 1 outie R2C3 = 1 innie R1C4 + 6, R1C4 = {123}, R2C3 = {789}

7. 45 rule on N8 1 outie R8C3 = 1 innie R9C4, no 1 in R8C3

8. 45 rule on D\ 1 innie R5C5 = 1 outie R4C5 + 4, R4C5 = {45}, R5C5 = {89}

9. 45 rule on D/ 1 innie R5C5 = 1 outie R6C5 + 2, R6C5 = {67}
[An optimised walkthrough would start with steps 8 and 9, either before or after step 2. I got them fairly quickly after doing the more routine 45s. Maybe the fact that it’s a killer-X with diagonal and near-diagonal cages should have made me look at 45s on the diagonals right at the start.]

10. R456C5 (step 2) = {579} (only remaining combination) = [597], 9 placed for both diagonals, clean-up: no 4 in R4C69 (step 4), no 2 in R6C6, no 4 in R6C9 (both step 5), no 4 in R7C1
10a. R5C5 = 9 -> R5C34 = {14/23}
10b. 5 on D\ locked in R7C7 + R8C8 + R9C9, locked for N9
10c. 7 on D/ locked in R3C7 + R2C8 + R1C9, locked for N3

11. R5C126 (step 1) = {678} (only remaining combination), locked for R5, 7 also locked for N4, clean-up: no 3 in R3C1
11a. 5 in R5 locked in R5C789, locked for N6, clean-up: no 4 in R6C6 (step 5)
11b. 4 in N5 locked in R456C4, locked for C4

12. R456C6 (step 3) = {128/236} -> R4C6 = 2, placed for D/, R6C6 = {13}, R4C9 = 7 (step 4), clean-up: no 8 in R3C1, no 3 in R5C3 (step 10a), no 3 in R6C9 (step 5)

13. 14(4) cage at R1C9 must contain 2,7 = {1247}, 1,4 locked for D/ and N3
13a. 20(3) cage in N3 = {389/569}, 9 locked for N3

14. 29(5) cage at R6C4 = {35678} (only remaining combination), 5 locked for N7, clean-up: no 6 in R6C2

15. 20(4) cage at R6C6 must contain 5 = {1568/3458} (cannot be {2567} because R6C6 only contains 1,3), no 2,7, 8 locked for D\ and N9
15a. R6C6 = {13} -> no 1,3 in R7C7 + R8C8 + R9C9
15b. 2,7 on D\ locked in R1C1 + R2C2 + R3C3, locked for N1, clean-up: no 1 in R1C4 (step 6), no 1,6 in 8(2) cage, no 3,8 in R4C2

16. Naked pair {35} in 8(2) cage, locked for N1

17. 3 on D\ locked in R4C4 + R6C6, locked for N5, clean-up: no 2 in R5C3 (step 10a)
17a. Naked pair {68} in R5C6 + R6C4, locked for N5
17b. 3 on D/ locked in R7C3 + R8C2 + R9C1, locked for N7, clean-up: no 8 in R6C2, no 7 in 10(2) cage

18. Naked pair {14} in R5C34, locked for R5
18a. Naked triple {235} in 10(3) cage at R5C7, locked for N6

19. 21(5) cage at R1C1 must contain 2,5,7 = {12567/23457}
19a. 3 of {23457} must be in R4C4 -> no 4 in R4C4

20. Naked pair {13} in R4C4 + R6C6, locked for D\ and N5 -> R5C4 = 4, R5C3 = 1, clean-up: no 9 in R3C1

21. Min R4C3 + R5C2 = 9 -> max R6C3 = 5 (15(3) cage cannot be [366]), no 6,8,9 in R6C3

22. 15(3) cage at R1C2 = {249/348} (cannot be {168} because R1C4 only contains 2,3), no 1,6, 4 locked for R1 and N1 -> R1C9 = 1

23. R3C1 = 1 (hidden single in N3), R4C2 = 9, clean-up: no 2 in R7C1

24. Naked triple {267} in R1C1 + R2C2 + R3C3, 6 locked for D\, R4C4 = 1 (step 19), R6C6 = 3, R5C6 = 6 (step 12), R6C4 = 8, placed for D/, R6C9 = 6, clean-up: no 8 in R7C1
24a. Naked pair {48} in R4C78, locked for R4 and N6
24b. Naked triple {458} in R7C7 + R8C8 + R9C9, 4 locked for N9

25. 18(3) cage in N4 = {468/567} (cannot be {378} because R6C1 only contains 2,4,5), no 2 -> R4C1 = 6, R4C3 = 3, clean-up: no 5 in R6C2, no 4 in R7C2
25a. Naked pair {35} in R29C1, locked for C1 -> R6C1 = 4, R5C1 = 8, R5C2 = 7, R6C2 = 2, R7C1 = 9, R6C3 = 5, R7C3 = 6, R8C1 = 2, R7C2 = 8, R1C1 = 7, R2C2 = 6, R3C3 = 2, R1C2 = 4

26. R9C2 = 1 -> R9C34 = 10 = [46/73]

27. 17(3) cage at R7C4 = {467} (only remaining combination because R8C3 only contains 4,7) -> R8C3 = 4, R78C4 = [76]

and the rest is naked singles and a cage sum.

Alright, here's a a slightly harder version of V1 which starts quite easy with even more early placements but needs some thinking afterwards to be cracked.

Assassin 176 V1.5


Note: No repeat on the diagonals! (Not required for uniqueness)

3x3:d:k:5377:3849:3849:3849:3853:3853:5138:5138:3605:2056:5377:5642:5642:3853:3598:5138:3605:5142:2567:2056:5377:5642:3598:3598:3605:5142:5142:6404:2567:3331:5377:5377:3605:7441:4632:5142:6404:6404:3331:3331:7441:7441:7441:7441:4632:6404:2821:3331:7426:7426:5140:7441:4632:4887:2821:2566:7426:4363:2831:2831:5140:4887:4887:2566:7426:4363:4363:4624:2831:3859:5140:4887:7426:2828:2828:2828:4624:4624:3859:3859:5140:


Estimated rating: Easy 1.25 - 1.25.
SS Score: 1.35.

Thanks Afmob for this V 1.5 : since he could post it because I was volunteer for the next assassin, I had to post a WT.
This version can be solved quite quickly, but I had to use a quite hard step, which justifies the difficulty.
It's a nice puzzle ; a kind of one-trick pony


ASSASSIN 176 v1.5 Solving path

One hard step : 4)c). A kind of step by contradiction, but I have no problem with this kind of move when it is not trial and error step for a neat move.

1)a) Innies-outies for D/ : r6c5=r5c5-2
b) Innies-outies for D\ : r4c6=r5c5-4
c) Outies for c1234 : 12=r4c5+r6c5=2r5c5-6 from steps a)+b) so 18=2r5c5
=> r5c5=9, r6c5=7, r4c6=5

2)a) 7 locked for D/ at 14(4) : {1247} locked for D/ => 29(5) at D/ : {35678}
=> {35} locked for n7 at r7c3+r8c2+r9c1
b) Outies for n78 : r6c2+r6c4=h10(2)=[46/28]
=> 11(2)n4=[47/29]
c) Outies for n3 : r4c6+r4c9=h9(2)=[18/27]
=> {47} locked for n3 at r1c9+r2c8+r3c7
=> 20(3)n3={389/569} : 9 locked for n3
d) Outies for n9 : r6c6+r6c9=h9(2) : no 2, no 9.
e) 9 locked for c8 and n6 at r4c8+r6c8
=> 9 locked for n3 and c7 at r12c7
=> 9 locked for c9 and n9 at r78c9
=> Hidden single for r9 : r9c6=9

3)a) Innies-outies for n2 : r2c3=6+r1c4 : r2c3=(789), r1c4=(123)
b) 9 locked for c4 at r23c4 : r2c3 <> 9 → r1c4=(12)
c) Innies-outies for n12 : r3c1=r4c4 :
=> r3c1<>7,9
=> r1c1+r2c2+r3c3+r3c1=h16(4) with no 5,9 : {1348/1267/2347}
d) 9 locked for n1and r1 at rc23:
=> 15(3)n1={15/24}9
e) Hidden singles : r2c7=9, and r3c4=9
=> r2c34=[76/85]

4)a) r9c4<>7 since r9c23<>{13} (cage combination for 11(3))
=> 7 locked for c4 at r78c4 :no 3,5 for 17(3) at n8.
b) Innies-outies for n8 : r8c3=r9c4+1 : r8c3<>3,5 => r9c4<>2,4
c) No 5 at r9c4 : like this. 5 at r9c4 => r8c3=6 (step 4)b)) => r6c4=6 (only place for digit 6 at D/ ) which is impossible since r69c4=[65] would block cell r2c4=(56)
=> Hidden single for c4 :r2c4=5

The puzzle is now cracked.


5)a) r2c3=8 => (step 3)a)) r1c4=2, r1c23={49} locked for r1 and n1.
b) Last combo for h16(4)n1 : {1267}. r3c1=r4c4=(16)
=> hidden single : r3c2=5, r2c1=3
c) Innies for n8 : r7c4+r8c4+r9c4=h16(3) with 7 locked : h16(3)=7{18/36}. But {178} blocks cells r4c4+r6c4=(16)+(68), so h16(3)={367} locked for c4 and n8. Hidden single :r9c4=3, r78c4={67} => r8c3=4 (cage sum)
d) r4c4=1=r1c3, => r4c2=9
e) 25(4)n4 <> 9 : {4678} locked for n4

The rest is straightforward.

manu, as ingenious as your critical move (step 4c) is, I don't think you have found the "correct" breakthrough step which justifies Afmob's rating of 1.25 (easy).


But there is actually a much much easier move at that stage on offer:


Also, don't know why but my browser can't display Afmob's images at all. Is my ISP's range of IP addresses being blacklisted by his image hosting site's server? Would appreciate if he could use a more "internationally accessible" image hosting site such as imageshack or tinypic.

_________________
ADYFNC HJPLI BVSM GgK Oa m

Thanks Afmob for a nice V1.5. At first I felt it was hard work but then started to make better progress and it turned out to be easier than I'd expected. I finally cracked it the same way as in udosuk's message although it took me longer to reach that position. Manu's step 4c was a neat way to make a short walkthrough.


Here is my walkthrough for A176 V1.5. Thanks Afmob and Ed for your comments and corrections.

Prelims

a) 8(2) cage in N1 = {17/26/35}, no 4,8,9
b) 10(2) cage at R3C1 = {19/28/37/46}, no 5
c) 11(2) cage at R6C2 = {29/38/47/56}, no 1
d) 10(2) cage in N7 = {19/28/37/46}, no 5
e) 22(3) cage at R2C6 = {589/679}, CPE no 9 in R2C56
f) 20(3) cage in N3 = {389/479/569/578}, no 1,2
g) 11(3) cage at R7C5 = {128/137/146/236/245}, no 9
h) 11(3) cage at R9C2 = {128/137/146/236/245}, no 9
i) 14(4) cage at R1C9 = {1238/1247/1256/1346/2345}, no 9
j) 13(4) cage at R4C3 = {1237/1246/1345}, no 8,9, CPE no 1 in R5C12

1. 45 rule on C1234 2 outies R46C5 = 12 = {39/48/57}, no 1,2,6

2. 45 rule on D\ 1 innie R5C5 = 1 outie R4C5 + 4, R4C5 = {345}, R5C5 = {789}

3. 45 rule on D/ 1 innie R5C5 = 1 outie R6C5 + 2, R6C5 = {57}, no 8 in R5C5, clean-up: no 4 in R4C5 (step 2)

4. R46C5 = 12 = [57], R5C5 = 9 (step 2), placed for both diagonals, clean-up: no 4 in R7C1
4a. 5 on D\ locked in R7C7 + R8C8 + R9C9, locked for N9

5. 45 rule on N3 2 outies R4C69 = 9 = {18/36}/[27], no 4, no 2,9 in R4C9

6. 45 rule on N9 2 outies R6C69 = 9 = {18/36}/[45], no 2, no 4,9 in R6C9

7. 45 rule on N2 1 outie R2C3 = 1 innie R1C4 + 6, R1C4 = {123}, R2C3 = {789}
7a. 45 rule on N2 3 outies R1C23 + R2C3 = 21 = {489/579/678}, no 1,2,3

8. 45 rule on N8 1 outie R8C3 = 1 innie R9C4, no 1 in R8C3

9. 7 on D/ locked in 14(4) cage at R1C9 = {1247} (only remaining combination), locked for D/, 4,7 also locked for N3, clean-up: no 1,3,6 in R4C9 (step 5)

10. 29(5) cage in R6C4 = {35678}, 5 locked for N7, clean-up: no 6 in R6C2, no 4 in R9C4 (step 8)

11. 20(3) cage in N3 = {389/569}, 9 locked for N3

12. 18(3) cage in N8 cannot be {279/459/567} because no 5,7,9 in R89C5, no 2,5 in 18(3) cage
[On this occasion I've deleted my permutation analysis on the remaining combinations. It proves unnecessary after steps 19 and 21. This may be a one-off. My natural inclination after eliminating combinations, particularly if they result in candidates eliminations, is to do permutation analysis on the remaining combinations to see whether I can make any further eliminations.]

13. R4C69 (step 5) = [18/27]
13a. 45 rule on N12 2 remaining outies R4C24 = 10 = [46/64/73/91] (cannot be {28} which clashes with R4C69), no 2,8, no 1,3 in R4C2, clean-up: no 2,7,8,9 in R3C1
13b. 9 in R3 locked in R3C46, locked for N2

14. 45 rule on N78 2 remaining outies R6C24 = 10 = [28/46], clean-up: R7C1 = {79}
14a. 29(5) cage in R6C4 = {35678}, 3 locked for N7, clean-up: no 7 in 10(3) cage in N7, no 2 in R9C4 (step 8)

15. 45 rule on N3569 3 innies R456C4 = 13 = {148/238/346}
15a. R6C4 = {68} -> no 6 in R45C4, clean-up: no 4 in R4C2 (step 13a), clean-up: no 6 in R3C1

16. 45 rule on N8 3 outies R8C3 + R9C23 = 12 = {129/147/246}, no 8, clean-up: no 7 in R9C4 (step 8)

17. 9 in N1 locked in R1C23 + R2C3 (step 7a) = {489/579}, no 6

18. 21(5) cage at R1C1 must contain one of 7,8 in N1 (from remaining combinations with 5 locked and no 9), R1C23 + R2C3 must contain two of 7,8,9
18a. Killer triple 7,8,9 in 21(5) cage and R1C23 + R2C3, locked for N1, clean-up: no 1 in 8(2) cage in N1

[At this stage I could use the “clone” move
45 rule on N12 1 remaining outie R4C4 = 1 innie R3C1
1 in N1 locked in R1C1 + R2C2 + R3C13 -> 1 locked in R1C1 + R2C2 + R3C3 + R4C4, locked for D\.
However I’ll try to find simpler moves.]

19. 9 in N6 locked in R46C8, locked for C8
19a. 9 in C9 locked in R78C9, locked for N9
19b. 19(4) cage at R6C9 = 9{127/136/145/235}, no 8, clean-up: no 1 in R6C6 (step 6)

20. 45 rule on C789 3 remaining outies R456C6 = 11 = {128/146/236}
20a. 8 of {128} must be in R6C6 -> no 8 in R5C6
20b. 8 in N5 locked in R6C46, locked for R6

21. R9C6 = 9 (hidden single in R9), R89C5 = 9 = {18/36}, no 4
21a. R3C4 = 9 (hidden single in R3), R2C34 = 13 = [76/85], no 7,8 in R2C4, clean-up: no 3 in R1C4 (step 7)
21b. R2C7 = 9 (hidden single in R2), R1C78 (step 11) = {38/56}

22. R1C23 + R2C3 (step 17) = {489/579}
22a. R2C3 = {78} -> no 7,8 in R1C23

23. 7 in C4 locked in R78C4, locked for N8 and 17(3) cage at R7C4, no 7 in R8C3, clean-up: no 6 in R9C4 (step 8)
23a. 45 rule on N8 3 innies R789C4 (must contain 7) = 16 = {178/367/457}, no 2
23b. 3,5 of {367/457} must be in R9C4 -> no 3,5 in R78C4
[Alternatively the last sub-step could have come from combinations for 17(3) cage containing 7.]

24. 45 rule on N2 2 remaining innies R12C4 = 7 = [16/25]
24a. 15(3) cage in N2 = {168/258/348} (cannot be {267} which clashes with R12C4, cannot be {456} which clashes with R2C4, cannot be {357} because 5,7 only in R1C6), no 7, 8 locked for N2
24b. 5 of {258} must be in R1C6 -> no 2 in R1C6
24c. 1,2 of {168/258} must be in R1C56 (R1C56 cannot be {58/68} which clash with R1C78), no 1,2 in R2C5

25. 7 in N2 locked in 14(3) cage = {167/257/347}
25a. 2 of {257} must be in R3C5 -> no 2 in R23C6

26. 7 in R1 locked in R1C19
26a. 45 rule on R1 2 innies R1C19 = 1 remaining outie R2C5 + 4
26b. Min R1C19 = 8 -> min R2C5 = 4
26c. No 5 in R1C19 -> R1C19 cannot total 12 -> no 8 in R2C5
26d. R2C5 = {46} -> R1C19 = 8,10 = {17/37}, no 2,4,6,8

27. 8 in N2 locked in R1C56, locked for R1, clean-up: no 3 in R1C78 (step 21b)
27a. Naked pair {56} in R1C78, locked for R1 and N3, clean-up: no 2 in R1C5 (step 24a)

28. R1C4 = 2 (hidden single in R1), R2C4 = 5 (step 24), R2C3 = 8 (step 21a), clean-up: no 3 in R3C2, no 6 in R8C3 (step 8), no 4 in R78C4 (step 23a)
28a. Naked pair {49} in R1C23, locked for R1 and N1, clean-up: no 6 in R4C2, no 4 in R4C4 (step 13a)

29. R5C4 = 4 (hidden single in C4), clean-up: no 5 in R6C9 (step 6)
29a. 13(4) cage at R4C3 = {1246/1345}, no 7, 1 locked for C3 and N4

[Clean-up omitted from here.]
30. 21(5) cage at R1C1 = {12567} (only remaining combination) -> R4C4 = 1, R1C1 = 7, both placed for D\, naked pair {26} in R2C2 + R3C3, locked for N1 and D\, R2C1 = 3, R3C12 = [15], R1C9 = 1, R4C6 = 2, R2C9 = 2, R2C2 = 6, R3C3 = 2, R2C5 = 4, R2C8 = 7, R2C6 = 1, R3C7 = 4, R4C9 = 7 (step 5), R4C2 = 9, R1C23 = [49], R6C2 = 2, R7C1 = 9, R8C3 = 4, R9C4 = 3 (step 8)
30a. R8C3 = 4 -> R78C4 = 13 = {67}, locked for C4 and N8 -> R6C4 = 8, placed for D/, R6C6 = 3, placed for D\
30b. R9C4 = 3 -> R9C12 = 8 = {17}, locked for R9 and N7

and the rest is naked singles.