Thanks Afmob for another nice Assassin!
manu wrote:
There is no neat cracking move in this WT.
Maybe not but there were still some neat moves in it. I liked the "see each other" moves in steps 2a and 2e, which would become even more important if there was a V1.5 or V2 with the same cage pattern, and also the "must be equal to one of" move in step 4e.
Here is my walkthrough for A179. I hope I got all my references to early steps correct; I had to renumber a lot of my steps after I found that I had two step 9s.
Prelims
a) 11(2) cage at R1C1 = {29/38/47/56}, no 1
b) R12C6 = {16/25/34}, no 7,8,9
c) R23C1 = {29/38/47/56}, no 1
d) R23C9 = {19/28/37/46}, no 5
e) R5C12 = {39/48/57}, no 1,2,6
f) R5C89 = {17/26/35}, no 4,8,9
g) R78C1 = {39/48/57}, no 1,2,6
h) R78C9 = {69/78}
i) R89C4 = {16/25/34}, no 7,8,9
j) 4(2) cage in N9 = {13}
k) 9(3) cage at R3C2 = {126/135/234}, no 7,8,9
l) 10(3) cage at R6C1 = {127/136/145/235}, no 8,9
m) 11(3) cage at R6C4 = {128/137/146/236/245}, no 9
n) 27(4) cage at R4C3 = {3789/4689/5679}, no 1,2
o) 14(4) cage at R4C7 = {1238/1247/1256/1346/2345}, no 9
1. Naked pair {13} in 4(2) cage in N9, locked for N9 and D\, clean-up: no 8 in 11(2) cage at R1C1
2. 45 rule on N3 1 outie R4C6 = 1 innie R3C8 + 7, R3C8 = {12}, R4C6 = {89}
2a. 45 rule on N3 3 outies R4C689 = 23 = {689}, locked for R4, 6 also locked for N6, clean-up: no 2 in R5C89
2b. 45 rule on N3 3 innies R2C8 + R3C78 = 11 = {128/137/146/236/245}, no 9
3. R5C12 = {39/48} (cannot be {57} which clashes with R5C89), no 5,7
4. 45 rule on N7 3 outies R6C124 = 10 = {127/136/145/235}, no 8
5. 45 rule on N2 1 innie R1C4 = 1 outie R4C5 + 6, R1C4 = {789}, R4C5 = {123}
6. Killer quad 6,7,8,9 in R23C9, R4C9 and R78C9, locked for C9, clean-up: no 1 in R5C8
6a. Max R6C9 = 5 -> min R67C8 = 11, no 1 in R6C8
7. 45 rule on N6 3(2+1) outies R3C8 + R5C6 + R7C8 = 9
7a. Min R37C8 = 3 -> max R5C6 = 6
7b. Min R3C8 + R5C6 = 2 -> max R7C8 = 7, clean-up: no 2,3 in R6C8 (max R67C8 = 11, step 6a)
8. 45 rule on N12 1 innie R3C3 = 3 outies R4C125 + 2
8a. Min R4C125 = 6 -> min R3C3 = 8
8b. R3C3 = {89} -> R4C125 = 6,7 = {123/124}, no 5, 1,2 locked for R4
9. 45 rule on N1 2 innies R3C23 = 1 outie R1C4 + 5
9a. Min R1C4 = 7 -> min R3C23 = 12, no 1,2
[I originally saw this before step 8 but it’s simpler this way round.]
10. Killer quad 1,2,3,4 in R4C12, R5C12 and R6C12 (must contain at least one of 1,2,3,4), locked for N4
[There’s a hidden killer quad at this stage but it’s unnecessary after the next 2 steps.]
11. 27(4) cage at R4C3 = {5679} (only remaining combination, cannot be {3789/4689} because R456C3 = {689/789} clash with R3C3), no 3,4,8, CPE no 9 in R5C12, clean-up: no 3 in R5C12
11a. 9 in N4 locked in R56C3, locked for C3 and 27(4) cage (no 9 in R5C4) -> R3C3 = 8, placed for D\, clean-up: no 3 in R23C1, no 2 in R2C9
12. Naked pair {48} in R5C12, locked for R5 and N4
12a. Naked triple {123} in R4C125, locked for R4
13. 45 rule on N1 1 outie R1C4 = 1 remaining innie R3C2 + 3, no 3 in R3C2
14. 45 rule on N9 2 innies R7C78 = 1 outie R9C6 + 3
14a. Min R7C78 = 6 -> min R9C6 = 3
14b. 45 rule on N8 1 outie R6C5 = 1 innie R9C6 -> min R6C5 = 3
15. 45 rule on N4 3(2+1) outies R3C2 + R5C4 + R7C2 = 13
15a. Min R3C2 + R5C4 = 9 -> max R7C2 = 3 (R37C2 cannot be [44]
16. 1,3 in N1 locked in 18(4) cage at R1C2 = {1359/1368}, no 2,4,7, clean-up: no 4 in R3C2 (step 12)
16a. 8,9 must be in R1C4 -> no 9 in R1C2
16b. 9(3) cage at R3C2 = {126/135}, 1 locked for R4 and N4
17. Naked quad {1356} in R1C23 + R2C3 + R3C2, locked for N1
[Alternatively both 11(2) cages in N1 cannot contain {56} which clashes with R3C2.]
18. 4 in C3 locked in R789C3, locked for N7, clean-up: no 8 in R78C1
18a. Killer pair 7,9 in R23C1 and R78C1, locked for C1, clean-up: no 2,4 in R2C2
18b. Killer pair 2,4 in R1C1 and R23C1, locked for C1 -> R5C12 = [84]
19. 45 rule on N7 1 outie R6C4 = 1 innie R7C2 -> R6C4 = {123}
20. Min R4C7 + R5C67 = 7 -> max R6C7 = 7
21. 10(3) cage at R6C1 = {136/235} (cannot be {127} because R6C1 only contains 3,5,6), no 7, CPE no 3 in R4C2
21a. Killer pair 1,2 in R4C2 and R67C2, locked for C2
21b. 1 in N1 locked in R12C3, locked for C3
21c. 7 in N4 locked in R456C3, locked for C3 and 27(4) cage, no 7 in R5C4
21d. R6C124 (step 4) = {136/235}, 3 locked for R6, clean-up: no 3 in R9C6 (step 13b)
[There’s now an interesting “clone” move.
1 in N7 locked in R7C2 + R9C1
45 rule on N7 1 outie R6C4 = 1 innie R7C2 -> 1 locked in R6C4 + R9C1, locked for D/.]
22. 23(4) at R8C7 = {2489/2579/2678/4568}
22a. All combinations must have one of 6,7,8,9 in R9C6 (to avoid clash with R78C9) -> R9C6 = {6789}, clean-up: no 4,5 in R6C5 (step 13b)
23. 11(3) cage at R6C4 = {128/137/146/236/245}
23a. 4 of {245} must be in R7C3 -> no 5 in R7C3
24. Max R89C3 + R9C2 = 20 (well actually less if one takes account of clashes with the 27(4) cage at R4C3) -> no 1 in R9C1
[I ought to have spotted this earlier.]
25. R7C2 = 1 (hidden single in N7) -> R6C12 = {36} (step 21), locked for R6 and N4 -> R4C12 = [12], R3C2 = 6 (step 16b), R5C4 = 6 (step 15), R4C5 = 3, R6C12 = [63], R6C4 = 1 (step 19), placed for D/, R1C2 = 5, R1C4 = 9 (step 13), clean-up: no 2 in R2C6, no 4 in R2C9, no 6 in R9C6 (step 14b)
25a. Naked pair {13} in R12C3, locked for C3
26. R7C7 = 6 (hidden single on D\), clean-up: no 9 in R78C9
26a. 5 on D\ locked in R4C4 + R5C5 + R6C6, locked for N5 -> R5C6 = 2, clean-up: no 5 in R2C6
26b. R1C1 = 2 (hidden single on D\), R2C2 = 9, placed for D\, clean-up: no 1 in R3C9
26c. Naked pair {78} in R78C9, locked for C9 and N9, clean-up: no 2,3 in R23C9
27. R3C8 + R5C6 + R7C8 = 9 (step 7)
27a. R5C6 = 2 -> R37C8 = 7 = [25], R4C6 = 9 (step 2), R4C89 = [86], R2C9 = 1, R3C9 = 9, R12C3 = [13], R9C9 = 3, R8C8 = 1, R1C9 = 4, placed for D/, R9C1 = 5, placed for D/, R5C5 = 7, placed for D/
and the rest is naked singles.