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The following Sudoku-X puzzle can be solved quickly.
(generated and displayed with Sudoku9Explainer)
+----------------------+----------------------+----------------------+
| 3 19 2 | 567 4 567 | 56 8 19 |
| 1468 489 5 | 689 2 689 | 16 7 3 |
| 68 7 69 | 35689 1 35689 | 2 4 569 |
+----------------------+----------------------+----------------------+
| 2 34589 3469 | 469 69 3489 | 134568 1356 7 |
| 7 348 1 | 346 5 2 | 9 36 468 |
| 4568 34589 3469 | 3489 7 1 | 34568 356 2 |
+----------------------+----------------------+----------------------+
| 145 1345 34 | 2 8 469 | 7 169 146 |
| 9 6 8 | 1457 3 457 | 145 2 145 |
| 14 2 7 | 14569 69 4569 | 134568 13569 468 |
+----------------------+----------------------+----------------------+ Sudoku-X
Update (Nov 15, 2025)
+----------------------+----------------------+----------------------+
| 3 1-9 2 | 567 4 567 | 56 8 19 | 9
| 1468 489 5 | 689 2 689 | 16 7 3 | 8
| 68 7 69 | 35689 1 35689 | 2 4 569 | 7
+----------------------+----------------------+----------------------+
| 2 34589 3469 | 469 69 3489 | 134568 1356 7 | 6
| 7 348 1 | 346 5 2 | 9 36 468 | 5
| 4568 34589 3469 | 3489 7 1 | 34568 356 2 | 4
+----------------------+----------------------+----------------------+
| 145 1345 34 | 2 8 469 | 7 169 146 | 3
| 9 6 8 | 1457 3 457 | 145 2 145 | 2
| 14 2 7 | 14569 69 4569 | 134568 13569 468 | 1
+----------------------+----------------------+----------------------+
a b c d e f g h i Sudoku_X
The one-stepper (pretty!) eliminates (9)b8 solving the puzzle with lclste.
Update (Nov 16, 2025)
+----------------------+----------------------+----------------------+
| 3 1-9 2 | 567 4 567 | 56 8 *19 | 9
| 1468 (489) 5 | 689 2 689 | 16 7 3 | 8
|(68) 7 (69) | 35689 1 35689 | 2 4 569 | 7
+----------------------+----------------------+----------------------+
| 2 34589 3469 |(469) (69) *3489 | 134568 1356 7 | 6
| 7 348 1 | 346 5 2 | 9 36 468 | 5
| 4568 34589 3469 |*3489 7 1 | 34568 356 2 | 4
+----------------------+----------------------+----------------------+
| 145 1345 34 | 2 8 469 | 7 169 146 | 3
| 9 6 8 | 1457 3 457 | 145 2 145 | 2
| 14 2 7 | 14569 69 4569 | 134568 13569 468 | 1
+----------------------+----------------------+----------------------+
a b c d e f g h i Sudoku_X
The move previously described is ALS-xz with transport with
ALS1:(9684)a6.b8.c6, ALS2:(469)d6.e6