Using the ‘Swordfish’ Sudoku solving technique
After you have tried all the easier strategies and find no new squares to solve (single possibility, only square, excluded hidden twins, naked twins, excluded subgroup), it may be worth looking out for Swordfishes.
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- Index of available guides
- Only Choice rule for gentle puzzles
- Only Square rule for gentle puzzles
- Single Possibility rule for gentle puzzles
- Two out of Three strategy for gentle puzzles
- Shared Subgroup rule for gentle and moderate puzzles
- Naked Twin rule for moderate puzzles
- Hidden Twin rule for tough puzzles
- X Wing rule for tough puzzles
- Swordfish rule for tough puzzles
- Alternate Pair rule for very tough puzzles
- Hook rule for very tough puzzles
- Trial and error rule for any puzzle
- Solving a gentle puzzle step by step
- Gentle puzzle solved using Only Choice and Only Square
- Moderate puzzle solved using some Twin and Sub-group logic
- Challenging puzzle solved using Hook and Sub-group logic
- Running a Dragon Tutorial
- Choosing a Dragon Tutorial
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