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Evil · Puzzle #656
9
5
6
8
8
1
6
5
7
3
3
4
1
8
9
8
5
7
6
6
4
7
3
9
9
1
4
Techniques used
- Hidden Single
- Naked Triple
- Hidden Triple
- Pointing Pair
- Hidden Pair
- Box-Line Reduction
- Naked Pair
- Forcing Chains
- Naked Single
- XY-Wing
- Simple Coloring
- XY-Chain