Prelims
a) R1C12 = {69/78}
b) R12C9 = {16/25/34}, no 7,8,9
c) R2C12 = {15/24}
d) R6C56 = {39/48/57}, no 1,2,6
e) R78C1 = {13}
f) R89C5 = {19/28/37/46}, no 5
g) R89C6 = {15/24}
h) R9C89 = {18/27/36/45}, no 9
i) 9(3) cage at R3C4 = {126/135/234}, no 7,8,9
j) 19(3) cage at R8C4 = {289/379/469/478/568}, no 1
k) 27(4) cage at R1C3 = {3789/4689/5679}, no 1,2
l) 28(4) cage at R3C8 = {4789/5689}, no 1,2,3
1a. Naked pair {13} in R78C1, locked for C1 and N7, clean-up: no 5 in R2C2
1b. 45 rule on N5 1 innie R6C4 = 6
1c. 31(5) cage at R6C3 contains 6 = {16789/35689/45679}, no 2
1d. 45 rule on R12 2 outies R3C79 = 16 = {79}, locked for R3 and N3
1e. 28(4) cage at R3C8 = {4789/5689}, 9 locked for N6, CPE no 8 in R6C8
1f. 45 rule on N3 2 innies R1C7 + R3C8 = 10 = [28/46/64]
1g. 45 rule on C12 2 innies R3C12 = 11 = [56/65/83]
1h. Killer pair 6,8 in R1C12 and R3C12, locked for N1
1i. 45 rule on C12 3 outies R345C3 = 11 = {128/137/146/245} (cannot be {236} which clashes with R3C12), no 9
1j. 9(3) cage at R3C4 = {126/234} (cannot be {135} which clashes with R3C12), no 5, 2 locked for R3 and N2
1k. Killer pair 3,6 in R3C12 and 9(3) cage, locked for R3, clean-up: no 4 in R1C7
1l. 45 rule on N1 using R3C12 = 11, 3 remaining innies R123C3 = 13 = {139/157} -> R3C3 = 1, R12C3 = {39/57}
1m. R2C12 = {24} (hidden pair in N1), locked for R2, clean-up: no 3,5 in R1C9
1n. 9(3) cage at R3C4 = {234} (only remaining combination), 3,4 locked for R3 and N2 -> R3C8 = 8, R1C7 = 2, clean-up: no 5 in R2C9, no 1 in R9C9
1o. Naked pair {56} in R3C12, locked for N1 and 22(5) cage at R3C1 -> R12C3 = {39}, locked for C3, 9 locked for N1 and 27(4) cage at R1C3
1p. R45C3 = 10 = {28}, locked for C3 and N4
1q. Naked pair {78} in R1C12, locked for R1
1r. R12C3 = 12 -> R2C45 = 15 = {78}, locked for R2
1s. R9C3 = 6 (hidden single in C3), clean-up: no 4 in R8C5, no 3 in R9C89
1t. R678C3 = {457}, R6C4 = 6 -> R7C4 = 9 (cage sum), clean-up: no 1 in R89C5
1u. R9C3 = 6 -> R89C4 = 13 = {58}, locked for C4 and N8 -> R1C4 = 1, R2C45 = [78], clean-up: no 6 in R2C9, no 4 in R6C6, no 2 in R89C5
1v. Killer pair 3,4 in R89C5 and R89C6, locked for N8
1w. 9 in N7 only in R8C2 + R9C12, locked for 22(4) disjoint cage at R2C4, no 9 in R2C4
2a. 2 in R6 only in R6C89, locked for 26(6) cage at R4C9, no 2 in R7C9
2b. 45 rule on N6 1 remaining outie R7C9 = 1 innie R6C7 + 1 -> R6C7 = {3457}, R7C9 = {4568}
2c. 26(6) cage at R4C9 = {123578/124568}
2d. 8 in N6 only in R4C9 + R5C79 + R6C89, locked for 26(6) cage, no 8 in R7C9 -> no 7 in R6C7
2e. Hidden killer pair 6,7 in 28(4) cage at R3C8 and 26(6) cage for N6, 28(4) cage contains one of 6,7 -> 26(6) cage must contain one of 6,7 in N6, no 6 in R7C9 -> no 5 in R6C7
2f. R9C89 = [18/27/72] (cannot be {45} which clashes with R7C9)
2g. 45 rule on C789 2 outies R7C56 = 8 = {17/26}
2h. R7C56 = 8 -> R6789C7 = 22 = {1489/3469/3568} (cannot be {1579/1678} because R6C7 only contains 3,4, cannot be {3478} which clashes with R9C89, cannot be {4567} which clashes with R7C56), no 7
2i. Consider permutations for R12C9 = [43/61]
R12C9 = [43] => R6C7 + R7C9 = [45]
or R12C9 = [61] => R2C7 = {35} => R6789C7 cannot be {3568}
-> R6789C7 = {1489/3469}, no 5, 4,9 locked for C7, 9 locked for N9
2j. R3C79 = [79]
2k. R4C7 = {56} -> 28(4) cage at R3C8 = {5689}, 5,6 locked for N6
2l. 26(6) cage = {123578}, 3 locked for N6 -> R6C7 = 4, R7C9 = 5, clean-up: no 8 in R6C6
2m. R6C56 = {39} (cannot be {57} which clashes with R6C3), locked for R6 and N5
2n. Naked pair {57} in R6C13, locked for N4, 7 locked for R6 -> R6C2 = 1, R6C89 = [28]
2o. 7 in N6 only in R45C9, locked for C9 -> R9C9 = 2, R8C9 = 7, clean-up: no 3 in R8C56
2p. 13(3) cage at R7C8 = {346} (only possible combination), 3,6 locked for N9
2q. Naked triple {189} in R789C7, 1 locked for C7 and 30(6) cage at R6C6 -> R5C7 = 3, clean-up: no 7 in R7C56
2r. Naked pair {17} in R45C9, 1 locked for C9 -> R12C9 = [43], R8C9 = 6, R8C5 = 7 -> R9C5 = 3, R6C56 = [93], clean-up: no 2 in R8C6
3a. 4 in C3 only in R78C3, locked for N7
3b. R4C2 = 3 (hidden single in N4) -> R8C2 + R9C12 = 19 = {289} (only possible combination) -> R8C2 = 2, R9C12 = {89}, locked for R9, 8 locked for N7
and the rest is naked singles.