Crane Sudoku Technique — AIC Pattern Guide

A Crane is an AIC technique that follows a in a along two adjacent , forming a paper bird shape.

How it works

Start by finding a strong link in a Box

This box has a on 6 — only two cells in the can be 6.

Do one of the 6 connect along a line?

All we need it s in a . It's okay that there are other 6's in the column.

Follow the adjacent line

A final along the opposite type finishes the Crane shape.

Spot the contradiction

If neither was 6, then the line would be invalid. It would have more than one 6.

One end must be 6

At least one of the two end cells must be 6.

Eliminate from shared peers

Safely remove 6 from any cell that sees both ends.

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Start by finding a strong link in a Box
This box has a on 6 — only two cells in the can be 6.
2
3
4
6
3
4
6
3
6
8
5
6
8
1
7
9
5
3
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Do one of the 6 connect along a line?
All we need it s in a . It's okay that there are other 6's in the column.
2
3
4
6
3
4
6
3
6
8
5
6
8
1
7
9
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3
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1
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Follow the adjacent line
A final along the opposite type finishes the Crane shape.
2
3
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4
6
3
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2
5
Spot the contradiction
If neither was 6, then the line would be invalid. It would have more than one 6.
2
3
4
6
3
4
6
3
6
8
5
6
8
1
7
9
5
3
6
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1
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1
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2
5
One end must be 6
At least one of the two end cells must be 6.
2
3
4
6
3
4
6
3
6
8
5
6
8
1
7
9
5
3
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9
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Eliminate from shared peers
Safely remove 6 from any cell that sees both ends.

All Hints

Unlock hints to find
the Crane on your board.

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