TsumegoFromGames83/Attempts

Sub-page of TsumegoFromGames83
[Diagram]
Options  

Dieter: Let's analyze this position somewhat systematically. Black a almost certainly leads to a ko of some kind. If Black covers the atari at b by playing around there, White will move into c. Let's look at these things in more detail:

[Diagram]
Black lives  

If White doesn't fight the ko, Black lives.

[Diagram]
Ko (often correct)  

Here we have the ko If Black wins the ko, taking the first line stone, it ruins the value of the White position on the left. Hence, playing the ko seems to be the best option. But White seems up for the risk, can Black do better?

[Diagram]
Miai?  

After W2, a and b are miai for the kill. At least, that's how it appears. But ...

[Diagram]
Not miai  

After black+circle-white+circle, the alleged miai B1-W2 and B3-W4, a move at a threatens to capture three to make an eye. It's important not to play there too soon, due to an imminent shortage of liberties. Instead B5 cuts. After W6, the throw in at B7 puts White in a clumsy shape.

unkx80: I still think B7 should be directly played at b... Slarty: Sort of agree, but it's the same

[Diagram]
Depends on outside  

The continuation depends on any nearby stones at the right side. However ...

[Diagram]
White strikes  

Instead of playing at B3, White can play W2 here. B3 looks like the obvious answer, but W4 completes the pulley tesuji: Black a will be answered by White b. Black is dead, but B3 neglects to use the stone and space above.

[Diagram]
Connect  

Connecting makes black alive in the corner, except when white reduces from the outside with a! The ko fight by playing a is similar to before.

[Diagram]
Excitement  
[Diagram]
Continuation outside  

White's attack is desperate but effective, and Black escapes only with favorable conditions outside. W5 can also pincer.

[Diagram]
Black's resistance  

Finally, Black can respond like this, cutting as before, careful of having enough liberties. This is actually good for Black.

[Diagram]
good variation  

Both colors have 3 external liberties, just like above.

[Diagram]
Punishment (depends on outside)  

White can always scurry away at a without gaining liberties, but if there is no escape, the liberty race results in a ko for the corner that White takes first. This result is probably considered much better for Black, because compared to starting the ko at the original position, Black gains the thick group on the outside.

[Diagram]
also correct  

So perhaps B1 can be considered to make life - although it still depends on ko and conditions on the left side, and playing ko is more natural. White trying to kill leaves bad aji.


Two possible solutions:

[Diagram]
Black lives, despite the initial atari  

Herman: What if white plays W2 at B5?

Funicular?: W2 at E1 also kills

[Diagram]
Here black also lives  

Herman: What if white plays W4 at B5?

[Diagram]
Then like this?  
[Diagram]
continuation  

wurfmaul: White can crawl further in this manner, but will die without supporting stones. Is this satisfactory?

Slarty: Yes almost certainly. Perhaps white can make it messy with another W2...

[Diagram]
What then?  

TsumegoFromGames83/Attempts last edited by Slarty on December 12, 2013 - 19:03
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