Solution Steps:

1. Row 5 / Column 1 → 5 (Naked Single)
2. Row 6 / Column 2 → 8 (Naked Single)
3. Row 3 / Column 3 → 3 (Hidden Single)
4. Row 7 / Column 1 → 8 (Hidden Single)
5. Row 7 / Column 6 → 2 (Hidden Single)
6. Row 7 / Column 8 → 1 (Hidden Single)
7. Row 4 / Column 9 → 5 (Hidden Single)
8. Row 6 / Column 6 → 5 (Hidden Single)
9. Row 9 / Column 3 → 5 (Hidden Single)
10. Row 8 / Column 7 → 5 (Hidden Single)
11. Row 8 / Column 9 → 8 (Hidden Single)
12. X-Wing: 3 r68 c48 => r2c8,r5c4<>3
13. Row 2 / Column 7 → 3 (Hidden Single)
14. 2-String Kite: 9 in r4c2,r7c5 (connected by r7c3,r8c2) => r4c5<>9
15. Finned X-Wing: 2 r34 c28 fr3c7 fr3c9 => r2c8<>2
16. Discontinuous Nice Loop: 2 r1c2 -2- r4c2 =2= r4c8 =7= r2c8 -7- r2c2 =7= r1c2 => r1c2<>2
17. Discontinuous Nice Loop: 4 r2c2 -4- r8c2 -9- r4c2 -2- r4c8 -7- r2c8 =7= r2c2 => r2c2<>4
18. Finned X-Wing: 4 r26 c48 fr2c5 fr2c6 => r1c4<>4
19. Discontinuous Nice Loop: 6 r2c4 -6- r4c4 -9- r4c2 -2- r2c2 =2= r2c4 => r2c4<>6
20. Discontinuous Nice Loop: 4 r2c8 -4- r6c8 -3- r6c4 =3= r5c5 =7= r4c5 -7- r4c8 =7= r2c8 => r2c8<>4
21. Locked Candidates Type 2 (Claiming): 4 in r2 => r13c5,r3c6<>4
22. XY-Chain: 6 6- r1c3 -2- r5c3 -9- r4c2 -2- r4c8 -7- r2c8 -6 => r1c7<>6
23. XY-Chain: 4 4- r2c6 -6- r2c8 -7- r4c8 -2- r4c2 -9- r8c2 -4 => r8c6<>4
24. W-Wing: 6/9 in r4c4,r8c6 connected by 9 in r48c2 => r4c6,r8c4<>6
25. Empty Rectangle: 6 in b3 (r8c68) => r3c6<>6
26. AIC: 4 4- r2c6 -6- r8c6 =6= r8c8 =3= r8c4 -3- r6c4 -4 => r2c4,r5c6<>4
27. Row 2 / Column 4 → 2 (Naked Single)
28. Row 2 / Column 6 → 4 (Hidden Single)
29. Row 8 / Column 6 → 6 (Hidden Single)
30. Locked Candidates Type 1 (Pointing): 6 in b9 => r3c7<>6
31. Naked Pair: 3,4 in r68c8 => r3c8<>4
32. X-Wing: 2 c28 r34 => r3c79<>2
33. 2-String Kite: 9 in r5c3,r8c4 (connected by r7c3,r8c2) => r5c4<>9
34. XY-Chain: 4 4- r5c4 -1- r5c6 -9- r5c3 -2- r4c2 -9- r8c2 -4- r8c8 -3- r6c8 -4 => r5c79,r6c4<>4
35. Row 6 / Column 4 → 3 (Naked Single)
36. Row 6 / Column 8 → 4 (Full House)
37. Row 8 / Column 8 → 3 (Naked Single)
38. Row 5 / Column 9 → 3 (Hidden Single)
39. Row 9 / Column 5 → 3 (Hidden Single)
40. XY-Wing: 1/4/9 in r5c46,r8c4 => r4c4<>9
41. Row 4 / Column 4 → 6 (Naked Single)
42. XY-Chain: 1 1- r1c4 -9- r8c4 -4- r8c2 -9- r4c2 -2- r5c3 -9- r5c6 -1 => r3c6,r5c4<>1
43. Row 5 / Column 4 → 4 (Naked Single)
44. Row 8 / Column 4 → 9 (Naked Single)
45. Row 1 / Column 4 → 1 (Full House)
46. Row 7 / Column 5 → 4 (Full House)
47. Row 8 / Column 2 → 4 (Full House)
48. Row 7 / Column 9 → 7 (Naked Single)
49. Row 1 / Column 2 → 7 (Naked Single)
50. Row 9 / Column 2 → 1 (Naked Single)
51. Row 7 / Column 7 → 6 (Naked Single)
52. Row 7 / Column 3 → 9 (Full House)
53. Row 9 / Column 1 → 6 (Full House)
54. Row 2 / Column 2 → 5 (Naked Single)
55. Row 5 / Column 3 → 2 (Naked Single)
56. Row 1 / Column 3 → 6 (Full House)
57. Row 4 / Column 2 → 9 (Full House)
58. Row 3 / Column 2 → 2 (Full House)
59. Row 1 / Column 1 → 4 (Naked Single)
60. Row 3 / Column 1 → 1 (Full House)
61. Row 2 / Column 5 → 6 (Naked Single)
62. Row 2 / Column 8 → 7 (Full House)
63. Row 5 / Column 7 → 7 (Naked Single)
64. Row 4 / Column 8 → 2 (Full House)
65. Row 3 / Column 8 → 6 (Full House)
66. Row 4 / Column 6 → 8 (Naked Single)
67. Row 4 / Column 5 → 7 (Full House)
68. Row 5 / Column 5 → 9 (Naked Single)
69. Row 5 / Column 6 → 1 (Full House)
70. Row 3 / Column 6 → 9 (Full House)
71. Row 1 / Column 5 → 8 (Naked Single)
72. Row 3 / Column 5 → 5 (Full House)
73. Row 3 / Column 9 → 4 (Naked Single)
74. Row 3 / Column 7 → 8 (Full House)
75. Row 1 / Column 7 → 2 (Naked Single)
76. Row 1 / Column 9 → 9 (Full House)
77. Row 9 / Column 9 → 2 (Full House)
78. Row 9 / Column 7 → 4 (Full House)