1. C456+N1
a) Innies+Outies N2: -5 = R4C4 - R1C4 -> R4C4 = (1234); R4C4 = (1234); R1C4 = (6789)
b) Innies+Outies N1: 2 = R1C4 - R2C3 -> R2C3 = (4567)
c) 6(3) = {123} locked for R6
d) Innies N5 = 13(3) -> R5C4 = (6789)
e) R7C56 <> 8,9 since it sees all 8,9 of N9

2. C789+N5
a) Innies N3456789 = 17(2+1): R4C9 <> 1,2,3,4 and R7C9 <> 1,2,3 since R4C4 <= 4
b) Innies+Outies N36: R4C9 = R7C8 = (56789)
c) 17(3) = 4{58/67} -> 4 locked for R6+N6

3. N45+R789 !
a) ! Using Outies R89 = 14(3): Innies+Outies C123456: R2C3 = R7C7 = (4567)
b) Outies R89 = 14(3) = {167/257/347/356}
c) Using Innies R89 = 15(3): Innies N9 = 20(3) = {479/569/578}
d) ! R7C7 <> 4 since it forces R7C89 = {79} and R7C56 = {37} (Overlapping cages)
e) Innies N9 = 20(3) = 5{69/78} since R7C78 <> 4,9 -> 5 locked for R7+N9
f) 10(3) = 1{27/36} -> 1 locked for N9
g) R7C56 <> 4 since it sees all 4 of N9

4. C456+N1
a) Outies R89 = 14(3) = {167/257/356}: R7C56 must have one of (67) since R7C56 <> 5
b) Using Innies N2 = 15(3) + Innies N5 = 13(3): Innies C4 = 17(3) <> {467} since it's blocked by Killer pair (67) of R7C56
c) Innies N25 = 18(3) <> 1 since {189} blocked by Killer pair (89) of Innies C4
d) Innies C123456: R2C3 = R7C7 <> 4
e) Innies+Outies N1: 2 = R1C4 - R2C3: R1C4 <> 6
f) Innies+Outies N2: -5 = R4C4 - R1C4: R4C4 <> 1
g) 10(3) = 1{27/36/45} -> 1 locked for C4+N2 since {235} blocked by R6C4 = (23); R23C4 <> 2,3,4 since R4C4 = (234)
h) Innies N25 = 18(3) = {279/369/378}
i) Innies C4 = 17(3) <> {359} since (39) is a Killer pair of Innies N25
j) Innies N2 = 15(3) = {159} locked for C4+N2 since {168} blocked by Killer pair (68) of Innies C4; R1C4 = 9

5. C456+N1
a) Outie N2 = R4C4 = 4
b) Innie N1 = R2C3 = 7
c) Innies+Outies C123456: R2C3 = R7C7 = 7
e) Outies R89 = 7(2) = {16} locked for R7+N8+29(6)
f) Innies C4 = 17(3) = {278} locked for C4+N8
g) R6C4 = 3, R5C4 = 6
h) 12(3) = {129} locked for C6+N5; R6C6 = 9
i) R7C6 = 6

6. C789
a) Innies of grid = 13(2) = {58} locked for C9
b) 17(3) = {458} since R7C8 = (58)
c) Naked triple (458) locked in R4C9 + R6C78 for N6
d) Innies+Outies N3: R3C7 = R4C8 = (1269)
e) 8 locked in R13C8 @ N3 for C8
f) R7C8 = 5, R7C9 = 8, R7C4 = 2, R6C8 = 4, R6C7 = 8
g) 5 locked in 9(3) @ N3 = {135} -> R2C8 = 1
h) R2C4 = 5, R3C4 = 1, R2C7 = 3, R1C7 = 5, R4C6 = 2

7. N127
a) 17(3) = {278/368/467} -> R1C5 = (26), R1C6 = (37)
b) 18(3) = 9{18/36}
c) 16(3) = 9{25/34} since 8{26/35} blocked by Killer pairs (38,68) of 18(3) -> R2C2 = 2, R3C2 = 9, R3C3 = 5
d) R5C5 = 8, R3C7 = 6
e) 31(6) = {234679} -> R6C1 = 6, R5C1 = 7; 3,4,9 locked for N7
f) 13(3) = {148} -> R1C1 = 1; 4,8 locked for C1+N1
g) R9C1 = 5, R8C1 = 2, R8C2 = 7, R8C4 = 8

8. R789
a) 10(3) = {136} -> R8C9 = 1
b) R8C3 = 6 -> R8C5 = 4, R9C6 = 3, R2C5 = 6, R1C5 = 2, R1C6 = 7 -> R2C6 = 8

9. Rest is singles without considering diagonals.

(Easy?) 1.5. I used Overlapping hidden cages.

Prelims

a) 9(3) cage at R1C7 = {126/135/234}, no 7,8,9
b) 10(3) cage at R2C4 = {127/136/145/235}, no 8,9
c) 20(3) cage at R4C5 = {389/479/569/578}, no 1,2
d) 6(3) cage at R6C2 = {123}
e) 10(3) cage at R8C8 = {127/136/145/235}, no 8,9

1. Naked triple {123} in 6(3) cage at R6C2, locked for R6
1a. Min R6C78 = 9 -> max R7C8 = 8

2. Max 10(3) cage at R2C4 + R6C4 = 13 must contain 1, locked for C4

3. 45 rule on N2 1 innie R1C4 = 1 outie R4C4 + 5 -> R1C4 = {6789}, R4C4 = {1234}

4. 45 rule on N1 1 outie R1C4 = 1 innie R2C3 + 2, R1C4 = {6789} -> R2C3 = {4567}

5. 45 rule on whole grid 3(1+2) innies R2C3 + R47C9 = 20
5a. Max R2C3 = 7 -> min R47C9 = 13, no 1,2,3 in R47C9

6. 45 rule on N36 1 outie R7C8 = 1 innie R4C9, no 9 in R4C9, no 1,2,3 in R7C8
6a. 17(3) cage at R6C7 = {458/467}, no 9
6b. 45 rule on N36 3 innies R4C9 + R6C78 = 17 = {458/467}, 4 locked for N6
6c. 45 rule on N3 1 outie R4C8 = 1 innie R3C7, no 4 in R3C7
6d. Min R47C9 = 13 (step 5a), max R4C9 = 8 -> min R7C9 = 5

7. 45 rule on N5 3 innies R456C4 = 13, max R46C4 = 7 -> min R5C4 = 6

8. 45 rule on R89 3 innies R8C7 + R9C78 = 15
8a. 45 rule on N9 (using R8C7 + R9C78 = 15) 3 remaining innies R7C789 = 20 = {389/479/569/578}, no 1,2
8b. R2C3 + R47C9 = 20 (step 5), R7C789 = 20, R7C8 = R4C9 (step 6) -> R2C3 = R7C7 = {4567}

9. R7C789 (step 8a) = {479/569/578}
9a. R8C7 + R9C78 (step 8) = 15 = {168/249/258/348} (cannot be {159/267/357/456} which clash with R7C789), no 7
9b. 10(3) cage at R8C8 = {127/136/235} (cannot be {145} which clashes with R7C789), no 4

10. R7C789 (step 8a) = 20
10a. 45 rule on R789 2 outies R56C1 = 2 innies R7C89
10b. Max R7C7 = 7 -> min R7C89 = 13 -> min R56C1 = 13, no 1,2,3 in R5C1

11. 4,8,9 in N9 only in R7C789 + R8C7 + R9C78, CPE no 4,8,9 in R7C56
11a. R7C789 (step 9) = {479/569/578}
11b. 45 rule on R89 3 outies R7C567 = 14 = {167/257/356} (cannot be {347} = {37}4 which clashes with R7C789 = 4{79}), no 4, clean-up: no 4 in R2C3 (step 8b), no 6 in R1C4 (step 4), no 1 in R4C4 (step 3)
11c. 9 of R7C789 = {569} must be in R7C9 -> no 6 in R7C9

12. R1C4 = R4C4 + 5 (step 3) -> R14C4 = [72/83/94]
12a. 10(3) cage at R2C4 = {136/145/235} (cannot be {127} = {17}2 which clashes with R14C4 = [72], IOD clash), no 7
12b. 4 of {145} must be in R4C4 -> no 4 in R23C4

13. R456C4 = 13 (step 7)
13a. 10(3) cage at R2C4 = {136/145/235}
13b. 3 of {235} must be in R4C4 (because R6C4 = 1, hidden single in C5, max R5C4 = 9 -> min R4C4 = 3) -> no 2 in R4C4, clean-up: no 7 in R1C4 (step 3), no 5 in R2C3 (step 4), no 5 in R7C7 (step 8b)
13c. R7C789 (step 11a) = {479/569/578}
13d. R7C7 = {67} -> no 6,7 in R7C89, clean-up: no 6,7 in R4C9 (step 6)

14. R1C4 = R4C4 + 5 (step 3) = [83/94], 10(3) cage at R2C4 (step 12a) = {136/145/235}
14a. R456C4 = 13 (step 7) = {139/247/346} (cannot be {148} = [481] which clashes with 10(3) cage = {15}4, cannot be {238} = [382] which clashes with R14C4 = [83]), no 8
14b. R456C4 = {139/247/346} = [391/472/463] -> 10(3) cage at R2C4 = {25}3/{15}4 (cannot be {16}3 which clashes with R456C4 = [391]), no 3,6 in R23C4, 5 locked for C4 and N2
14c. R1C4 + R456C4 = 8[391]/9[472]/9[463], 9 locked for C4
14d. 20(3) cage at R4C5 = {389/569/578} (cannot be {479} which clashes with R456C4), no 4
14e. 12(3) cage at R4C6 = {129/138/156/246} (cannot be {147/237/345} which clash with R456C4), no 7
14f. 8,9 of {129/138} must be in R6C6 -> no 8,9 in R45C6

15. R7C789 (step 11a) = {479/569/578}
15a. R7C567 (step 11b) = {167/257} (cannot be {356} = {35}6 which clashes with R7C789 = [659]), no 3, 7 locked for R7

16. R1C4 = R4C4 + 5 (step 3), R1C4 = R2C3 + 2 (step 4) -> R2C3 = R4C4 + 3, R2C3 = R7C7 (step 8b) -> R7C7 = R4C4 + 3 -> R4C4 + R7C7 = [36/47]
16a. R7C8 = R4C9 (step 6) which “sees” R4C4 -> R7C78 cannot be [74] -> R7C789 (step 11a) = {569/578} (cannot be {479} = [749]), no 4, 5 locked for R7 and N9, clean-up: no 4 in R4C9 (step 6)
16b. R7C567 (step 15a) = {167} (only remaining combination), locked for R7 and 29(6) cage at R7C5, 1 also locked for N8
16c. 4 in N6 only in R6C78, locked for R6
16d. 4 in C9 only in R123C4, locked for N3
16e. 4 in R7 only in R7C1234, locked for 31(6) cage at R5C1
16f. 9(3) cage at R1C7 = {126/135}, 1 locked for N3, clean-up: no 1 in R4C8 (step 6c)

17. 17(3) cage at R6C7 (step 6a) = {458} (only remaining combination, cannot be {467} because R7C8 only contains 5,8)
17a. Naked triple {458} in R4C9 + R6C78, locked for N6, clean-up: no 5,8 in R3C7 (step 6c)

18. R2C3 + R47C9 = 20 (step 5) = 6[59]/7{58}, 5 locked for C9

19. Hidden killer pair 6,7 in R5C4 and R89C4 for C4, R89C4 cannot contain both of 6,7 (which would clash with R7C56) -> R89C4 contains one of 6,7 and R5C5 = {67}
19a. Killer pair 6,7 in R89C4 and R7C56, locked for N8
[Cracked. The rest is fairly straightforward.]

20. R1C4 = 9 (hidden single in C4) -> R2C3 = 7 (step 4), R4C4 = 4 (step 3), placed for D\, R7C7 = 7 (step 8b), placed for D\, clean-up: no 7 in R4C8 (step 6c)
20a. Naked pair {16} in R7C56, locked for N8
20b. R5C4 = 6 (hidden single in C4) -> R6C4 = 3 (step 14a), placed for D/, clean-up: no 3 in R4C8 (step 6c)
20c. Naked triple {278} in R789C4, locked for C4 and N8
20d. Naked pair {15} in R23C4, locked for N2
20e. Naked pair {12} in R6C12, locked for N4

21. 10(3) cage at R8C8 = {136} (only remaining combination), locked for N9
21a. R8C7 + R9C78 (step 9a) = {249} (only remaining combination), locked for N9
21b. Naked pair {58} in R7C89, locked for R7 -> R7C4 = 2
21c. Naked pair {58} in R47C9, locked for C9
21d. Naked triple {349} in R7C123, locked for N7 and 31(6) cage at R5C1)

22. 8 in N3 only in R13C8, locked for C8 -> R67C8 = [45], R6C7 = 8, R47C9 = [58]

23. R5C4 = 6 -> R45C3 = 12 = {39}/[84]
23a. Killer pair 4,9 in R45C3 and R7C3, locked for C3

24. 20(3) cage at R4C5 (step 14d) = {578} (only remaining combination), locked for C5 and N5 -> R6C6 = 9, placed for D\, R45C6 = {12}, locked for C6 -> R7C56 = [16]

25. 5 in C6 only in R89C6, locked for 33(6) cage at R8C6
25a. Naked pair {78} in R78C4, CPE no 7,8 in R9C1
25b. 33(6) cage at R8C6 must contain 5 for C6 and 7,8 for R9 = {135789/345678}, no 2, 3 locked for N8

26. R7C1234 = {349}2 = 18 -> R56C1 = 13 = [76/85]
26a. 17(3) cage at R4C1 = {359/467} (cannot be {368} which clashes with R56C1, cannot be {458} because 4,5 only in R5C2), no 8
26b. 4,5 only in R5C2 -> R5C2 = {45}

27. 5 in C7 only in 9(3) cage at R1C7 = {135} -> R2C8 = 1, placed for D/, R23C4 = [51], R12C7 = [53]

28. R1C4 = 9 -> R1C23 = 9 = {18/36}, no 2,4
28a. 13(3) cage at R1C1 = {148/256/346} (cannot be {139/238} which clash with R1C23), no 9
28b. R3C2 = 9 (hidden single in N1) -> R2C2 + R3C3 = 7 = [25], 5 placed for D\ -> R5C5 = 8, placed for both diagonals, R46C5 = [75], R56C1 = [76]
28c. R4C6 = 2, placed for D/ -> R3C7 = 6, placed for D/
28c. 6 in N1 only in R1C23 = {36}, locked for R1 and N1 -> R1C1 = 1, placed for D\

29. 1 in R9 only in 33(6) cage at R8C6 = {135789}, no 4,6
29a. R8C5 = 4 (hidden single in N8), R1C5 = 2 -> R12C6 = 15 = [78]

and the rest is naked singles, without using the diagonals.

I'll rate my walkthrough for A322X at 1.5. I also used clashes of overlapping cages, some hidden, but I think step 16a, probably my hardest one, deserves the full 1.5.