All techniques
Locked Candidates (Claiming)
Working with Candidates12 / 32A line claims its digit for one box.
The mirror image of pointing: track a digit along a row or column. If every remaining candidate of that line falls inside one box, the line claims the digit for that box.
The box now knows its digit will come from that line, so the box's other two lines lose the digit entirely.
See it in action
123456789
2
7
1
8
123456789
4
3
5
1
5
123456789
123456789
123456789
3
123456789
123456789
7
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123456789
123456789
123456789
7
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123456789
1
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7
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3
9
123456789
123456789
123456789
1
2
123456789
123456789
7
1
4
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5
123456789
123456789
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1
123456789
5
8
123456789
7
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4
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123456789
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7
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123456789
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8
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123456789
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123456789
123456789
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4
123456789
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123456789
123456789
123456789
123456789
1
7
2
123456789
Step 1 of 4
The setup
Go line by line, digit by digit: are all of the digit's candidates in this row or column bunched inside a single box? Step through this real position to see it happen.
Practice
Find the line whose digit is confined to one box, and remove that digit from the box's other cells.
Drill 1 of 29Tap a cell, then the candidate digit you want to remove.