Easy Clone Sudoku
5
9
8
2
3
8
6
4
1
9
7
4
6
8
4
9
8
2
1
3
6
9
7
3
7
1
4
9
6
9
7
5
8
7
4
6
1
3
Clone A
Clone B
Both regions must have identical digits
How to play Clone Sudoku
Standard Sudoku rules apply. Two highlighted regions (Clone A in amber, Clone B in purple) must contain identical digit arrangements - Corresponding cells must hold the same digit. Placing a digit in one clone automatically constrains the same position in the other clone.
About Clone Sudoku
Difficulty
★★★★☆
4/5
Constraint Type
Clone Regions
Typical Givens
24–32
Avg. Solve (Medium)
22 min
Clone Sudoku marks pairs of regions (clones) on the grid. Each pair of clone regions must contain exactly the same arrangement of digits — if one clone has a 3 in its top-left cell, the other clone must also have a 3 in its corresponding cell. Clone constraints create powerful symmetry-based deductions that can resolve entire regions at once.
Solving Techniques
| Technique | Description | Level |
|---|---|---|
| Clone Pair Deduction | Any digit placed in one clone region immediately forces the same digit in the corresponding cell of the other clone region. | Beginner |
| Constraint Propagation | A clone placement propagates through standard row, column, and box constraints in both regions simultaneously. | Intermediate |
| Clone-Box Interaction | If both clone regions share boxes with heavily constrained cells, the clone constraint rapidly resolves entire boxes. | Intermediate |
| Mirror Elimination | When a digit is eliminated from a position in one clone region by standard logic, it can be eliminated from the same position in the other clone region. | Advanced |
| Multi-Clone Logic | With two clone regions, solving either provides equal information about both. Alternate deduction paths between clones for maximum efficiency. | Advanced |
Average Solve Time by Difficulty
Easy
10 min
Medium
22 min
Hard
42 min
Expert
72 min