TsumegoFromGames104/attempts

Sub-page of TsumegoFromGames104
[Diagram]

Dieter: Up to B9, Black lives. B1 sure is a surprising move. It can be found when desperately looking for a way to make B7 sente.

Tapir: Can't Black choose to start with B3 (then W4, B5, W6 and now B1) to avoid ko? What is the status of the center white group after Black lives on the edge?

hhw: Seems to me that if Black starts with B3, W4, and B5. White will play the next move where B7 is, and Black is caught.

Herman: No, in that case black will cut at W6 and capture 5 white stones. But if black plays B3-W4-B5-W6 and then B1, white will answer at B9.

[Diagram]

Var at W6

3 against 2

[Diagram]

Var at 2

This is the strongest resistance by White.

[Diagram]

Continuation

The result is a two stage ko for Black, while a direct ko for White.

xela: Isn't it an approach ko?

Bill: Yes, but the approach move is W6 in the previous diagram. ;) If Black omits B9 in this diagram, White can simply fill a Black liberty -- no ko.

Dieter: Huh? Black has to win the ko twice, White not.

[Diagram]

Failure

Black should accept the ko. If B3 here, he is short of liberties.

[Diagram]

Var @ 2

This is another variation where White cannot afford an attempt to kill Black, due to its sudden shortage of liberties, caused by the amazing 1-2 point throw-in.


This is a copy of the living page "TsumegoFromGames104/attempts" at Sensei's Library.
(OC) 2009 the Authors, published under the OpenContent License V1.0.
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