JCO Website (Puzzles for the manual solver)

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Recent Puzzles (*1*)

Puzzle SX66#14 (overall #131) (6x6 Sudoku-X (SE = 7.5); proposed Jyly 21, 2026)

I propose this Sudoku-X puzzle to be solved manually.

(generated and displayed with Sudoku6Explainer)

Sudoku-X

Hint (Update 1: easy placements, main position for analysis) 
+-------+-------+
| . . . | 6 . . |
| . . . | . . 1 |
+-------+-------+
| . . . | . . 6 |
| . . . | . . 4 |
+-------+-------+
| . . . | . . 5 |
| . . . | 3 . . |
+-------+-------+ X

There is a nice solution without using pencilmarks.
    
Update 1 (July 24, 2026)

+3 f6, +2 f1

  ,-----------------,
6 | . . . | 6  . *3 |
5 | . # . | .  .  1 |
  |-------+---------|
4 | . . # | .  .  6 |
3 | . . . | .  .  4 |
  |-------+---------|
2 | & . & | .  .  5 |
1 | . . . | 3  . *2 |
  '-----------------' X
    a b c   d  e  f

.(3)b5 = (3)c4, (3)a2=(3)c2 & (3)f6
 
=> +3b5!, +6e2, +3c2

  ,-------------------,
6 | .  .  . | 6  . *3 |
5 | . *3  . | .  .  1 |
  |---------+---------|
4 | .  .  . | .  .  6 |
3 | .  .  . | .  .  4 |
  |---------+---------|
2 | .  . *3 | . *6  5 |
1 | .  .  . | 3  . *2 |
  '-------------------' X
    a  b  c   d  e  f

Now, either (2)a2, or (2)b2.

What happens if we have (2)b2 ?

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Created: February 12, 2024

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