Pasos de la solución:

1. Fila 5 / Columna 8 → 6 (Hidden Single)
2. Fila 4 / Columna 1 → 6 (Hidden Single)
3. Fila 4 / Columna 4 → 7 (Hidden Single)
4. Fila 3 / Columna 8 → 8 (Hidden Single)
5. Fila 8 / Columna 9 → 6 (Hidden Single)
6. Fila 1 / Columna 8 → 2 (Hidden Single)
7. Fila 6 / Columna 9 → 3 (Hidden Single)
8. Fila 8 / Columna 7 → 7 (Hidden Single)
9. Fila 4 / Columna 8 → 1 (Hidden Single)
10. Fila 2 / Columna 7 → 9 (Hidden Single)
11. Fila 4 / Columna 9 → 4 (Hidden Single)
12. Fila 8 / Columna 3 → 3 (Hidden Single)
13. Fila 7 / Columna 7 → 3 (Hidden Single)
14. Naked Pair: 1,7 in r3c69 => r3c234<>1, r3c23<>7
15. Hidden Pair: 3,6 in r19c4 => r1c4<>1, r1c4<>9, r9c4<>5
16. XYZ-Wing: 1/4/5 in r12c1,r2c5 => r2c3<>1
17. Locked Candidates Type 2 (Claiming): 1 in c3 => r56c2,r6c1<>1
18. Discontinuous Nice Loop: 5 r2c3 -5- r4c3 -2- r4c5 =2= r6c5 =4= r2c5 -4- r3c4 -9- r1c5 =9= r1c2 =7= r2c3 => r2c3<>5
19. Hidden Rectangle: 1/5 in r1c19,r2c19 => r2c9<>1
20. Empty Rectangle: 1 in b8 (r2c15) => r7c1<>1
21. Discontinuous Nice Loop: 5 r5c3 -5- r4c3 -2- r4c5 =2= r6c5 =4= r2c5 -4- r3c4 -9- r3c3 =9= r6c3 =1= r5c3 => r5c3<>5
22. Discontinuous Nice Loop: 5 r6c1 -5- r1c1 -1- r2c1 =1= r2c5 =4= r6c5 =2= r4c5 -2- r4c3 -5- r6c1 => r6c1<>5
23. Discontinuous Nice Loop: 4 r6c3 -4- r6c5 =4= r2c5 -4- r3c4 -9- r3c3 =9= r6c3 => r6c3<>4
24. Discontinuous Nice Loop: 5 r6c3 -5- r4c3 -2- r4c5 =2= r6c5 =4= r2c5 -4- r3c4 -9- r3c3 =9= r6c3 => r6c3<>5
25. Discontinuous Nice Loop: 1 r8c5 -1- r2c5 -4- r3c4 -9- r7c4 =9= r8c5 => r8c5<>1
26. Locked Candidates Type 1 (Pointing): 1 in b8 => r7c2<>1
27. Hidden Rectangle: 1/5 in r1c12,r8c12 => r8c2<>5
28. Discontinuous Nice Loop: 4/5/8 r9c2 =7= r9c3 -7- r2c3 =7= r2c9 =5= r2c1 -5- r8c1 =5= r8c8 =9= r8c5 -9- r1c5 =9= r1c2 =7= r9c2 => r9c2<>4, r9c2<>5, r9c2<>8
29. Fila 9 / Columna 2 → 7 (Naked Single)
30. Fila 2 / Columna 3 → 7 (Hidden Single)
31. Fila 2 / Columna 9 → 5 (Naked Single)
32. Locked Candidates Type 1 (Pointing): 8 in b7 => r8c5<>8
33. Fila 8 / Columna 5 → 9 (Naked Single)
34. Fila 8 / Columna 8 → 5 (Naked Single)
35. Fila 9 / Columna 8 → 4 (Naked Single)
36. Fila 7 / Columna 8 → 9 (Full House)
37. Fila 9 / Columna 3 → 5 (Naked Single)
38. Fila 4 / Columna 3 → 2 (Naked Single)
39. Fila 4 / Columna 5 → 8 (Naked Single)
40. Fila 4 / Columna 7 → 5 (Full House)
41. Fila 9 / Columna 5 → 6 (Naked Single)
42. Fila 1 / Columna 5 → 1 (Naked Single)
43. Fila 9 / Columna 4 → 3 (Naked Single)
44. Fila 9 / Columna 6 → 8 (Full House)
45. Fila 1 / Columna 1 → 5 (Naked Single)
46. Fila 1 / Columna 9 → 7 (Naked Single)
47. Fila 3 / Columna 9 → 1 (Full House)
48. Fila 2 / Columna 5 → 4 (Naked Single)
49. Fila 2 / Columna 1 → 1 (Full House)
50. Fila 6 / Columna 5 → 2 (Full House)
51. Fila 3 / Columna 6 → 7 (Naked Single)
52. Fila 1 / Columna 4 → 6 (Naked Single)
53. Fila 1 / Columna 2 → 9 (Naked Single)
54. Fila 1 / Columna 6 → 3 (Full House)
55. Fila 3 / Columna 4 → 9 (Full House)
56. Fila 8 / Columna 1 → 8 (Naked Single)
57. Fila 8 / Columna 2 → 1 (Full House)
58. Fila 6 / Columna 7 → 8 (Naked Single)
59. Fila 5 / Columna 7 → 2 (Full House)
60. Fila 3 / Columna 3 → 4 (Naked Single)
61. Fila 3 / Columna 2 → 2 (Full House)
62. Fila 6 / Columna 1 → 4 (Naked Single)
63. Fila 7 / Columna 1 → 2 (Full House)
64. Fila 7 / Columna 2 → 4 (Full House)
65. Fila 5 / Columna 3 → 1 (Naked Single)
66. Fila 6 / Columna 3 → 9 (Full House)
67. Fila 6 / Columna 2 → 5 (Naked Single)
68. Fila 5 / Columna 2 → 8 (Full House)
69. Fila 6 / Columna 4 → 1 (Full House)
70. Fila 5 / Columna 6 → 5 (Naked Single)
71. Fila 5 / Columna 4 → 4 (Full House)
72. Fila 7 / Columna 4 → 5 (Full House)
73. Fila 7 / Columna 6 → 1 (Full House)