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Assassin 40 V2



3x3::k:4864:3585:3585:3585:6404:3589:3589:3589:3336:4864:4864:4363:6404:6404:6404:4623:3336:3336:7442:4363:4363:4885:4885:4885:4623:4623:7442:7442:7442:6429:6429:4885:4128:4128:7442:7442:2852:6429:6429:2855:2855:2855:4128:4128:3372:2852:1838:5679:5679:5681:5679:5679:1332:3372:2852:1838:3896:5681:5681:5681:3644:1332:3372:4671:4671:3896:4162:4162:4162:3644:3398:3398:4671:3913:3913:3913:4162:3661:3661:3661:3398:

After going through Ed's ever growing Killer archive I noticed that A40 V2 didn't have a walkthrough, so here is my take on it. This Assassin is cracked after the Killer quad in step 1 which is needed for important steps like 3a or 3b. Afterwards it's just one big mop-up.

A40 V2 Walkthrough:

1. R123 !
a) Innies R12 = 5(2) = {14/23}
b) Outies R12 = 30(4) = {6789} locked for R3
c) Innies+Outies N1: 5 = R1C4 - R3C1 -> R1C4 = (6789), R3C1 <> 5
d) Innies+Outies N3: R1C6 = R3C9 = (12345)
e) ! Killer quad (6789) locked in 19(3) + R3C23 for N1
f) Innies N1 = 9(3) = 3{15/24} -> 3 locked for N1
g) Innies R12 = 5(2): R2C7 <> 2

2. R456
a) Outies R1234 = 29(4) = {5789} locked for R5
b) 11(3) @ N5 = 6{14/23} -> 6 locked for R5+N5
c) Innies R1234 = 12(4) = 12{36/45} -> 1,2 locked for R4
d) 16(4): R5C78 <> 9 because it must be <= 13 -> R5C78 = 5{7/8}
-> 5 locked for R5+N6+16(4)
e) 16(4) = 15{28/37} -> 1 locked for R4
f) 9 locked in R5C23 for N4

3. C123
a) Naked quad (6789) locked in R3578C3 for C3
b) 25(4) = 59{47/38} -> 5 locked R4
c) Innies N7 = 12(4) = 12{36/45} -> 1,2 locked for N7

4. R456
a) Innies R1234 = 12(4) = {1245} locked for R4
b) 25(4) = {4579} -> 7 locked for R5+N4
c) Naked pair (58) locked in R5C78 for N6

5. C123
a) Killer pair (79) locked in R5C3+15(2) for C3
b) 17(3) must have one of (79) and it's only possible @ R3C2 -> R3C2 = (79)
c) Naked pair (79) locked in R35C2 for C2
d) 17(3) <> 1 because R3C3 = (68)
e) Innies N1 = 9(3) = {135} because R2C3 = (24) blocks {234}
-> 5 locked for R1+N1
f) 5 locked in 14(3) @ N1 = 5{18/36}

6. R123
a) 7,9 locked in 25(4) @ N2 = 79{18/36/45} <> 2
b) Innies R12 = 5(2): R2C7 <> 4
c) 19(4) = 5{149/239/248/347} because (789) only possible @ R4C5; R4C5 <> 3
-> 5 locked for R3+N2
d) 5 locked in 13(3) @ R2 = 5{17/26}
e) 25(4) = 79{18/36}
f) 4 locked in R2C123 @ R2 for N1
g) 4 locked in 14(3) @ R1C6 @ R1 = 4{19/28/37} <> 6
h) 29(6) = 1368{29/47} because R4C12 = (368)
-> 1 locked for R3, 8 locked for R4+N4
i) 19(4) = 35{29/47} -> 3 locked for R3+N2
j) R3C1 = 1
k) 14(3) @ N1 = {356} -> R1C4 = 6, 3 locked for R1

7. R789
a) 8 locked in R789C9 @ C9 for N9
b) 14(2) = {59} locked for C7+N9
c) Innies R89 = 14(2) = {59} -> R8C3 = 9 -> R7C3 = 6, R8C7 = 5
d) 18(3) = {378} locked for N7, 7 locked for C1
e) 7(2): R6C2 <> 1,4

8. N134
a) Hidden Single: R6C3 = 1 @ N4 -> 22(4) @ R6C3 = 1{489/579/678} <> 2,3
b) R5C7 = 8, R5C8 = 5, R3C3 = 8
c) Hidden Single: R1C8 = 8 @ N1 -> R1C67 = 6(2) = {24} locked for R1

9. R12+N5
a) 18(3) = {369} -> R2C7 = 3, R3C7 = 6, R3C8 = 9
b) 22(4) @ R6C3 = 19{48/57} -> 9 locked for R6+N5
c) Hidden Single: R4C9 = 9 @ N6
d) 29(6) = {123689} -> R3C9 = 2
e) R1C7 = 4, R1C6 = 2, R4C6 = 1, R4C7 = 2
f) Hidden Single: R5C9 = 1 @ R5 -> R67C9 = 12(2) = [48] -> R6C9 = 4, R7C9 = 8
g) R6C8 = 3 -> R7C8 = 2
h) Innies R12 = 5(2) = {23} -> R2C3 = 2

10. R789
a) 13(3) = {346} -> R8C8 = 4, {36} locked for N9
b) 14(3) = {167} because R9C78 = (17) -> R9C6 = 6, {17} locked for R9
c) 15(3) = 2{49/58} because R9C23 = (245) -> R9C2 = 2, R9C4 = (89)

11. Rest is singles.

Rating: 1.25. I used one Killer quad.