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Evil · Puzzle #408
2
1
8
5
3
1
7
4
9
1
4
2
3
4
5
1
8
3
9
7
5
1
4
3
9
7
Techniques used
- Hidden Single
- Naked Triple
- Naked Quad
- Pointing Pair
- Box-Line Reduction
- Skyscraper
- Naked Pair
- Finned X-Wing
- Forcing Chains
- Naked Single
- XY-Chain