Practise: Swordfish
Follow one digit only: which three rows or columns keep 4 inside the same three cross-lines?
The prepared notes show every 4 that matters. Find the three source lines whose candidates fit in the same three cross-lines; do not place a digit yet.
Example 1 of 4
Your turn first
Where can 4 no longer stay?
Look only at the prepared 4-notes. Find three rows or columns whose possible homes fit in the same three cross-lines, then identify the other 4-notes on those cross-lines to remove. Do not place a digit yet.
Remember
A Swordfish is simple: three source lines offer one digit only within the same three cross-lines. Those cross-lines must receive the digit from the pattern, so every other note for it there disappears. The Swordfish itself does not place a digit.
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