Practise: Finned Fish
This verified teaching position begins directly with a real Finned Fish pattern. Follow the chain, inspect the candidates and make the deduction before you continue.
You are at the verified key position. Use a hint to follow the chain link by link when you need support.
How to spot it
Start as if you were searching for an X-Wing or Swordfish: choose one digit and list its candidate positions on the lines. Look for two or three base lines whose candidates fit in the same cross-lines, except for one extra candidate. Verify that every fin and the matching Fish corner share one box. Only then inspect that cross-line inside the fin box for eliminations.
Put it to use
Where you will meet it
Expert grids are the only place this pattern regularly decides the solve. Bring your notes.
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