Ekisei Tsubiho 1

For lessons, as well as threads about specific moves, and anything else worth studying.
Bill Spight
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Re: Ekisei Tsubiho 1

Post by Bill Spight »

Click Here To Show Diagram Code
[go]$$Wc
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | 4 2 X X . O . .
$$ | X 1 . , X O . .
$$ | 3 5 . X . O . .
$$ | . X . O O . . .
$$ | . . . . . . . .
$$ +-----------------[/go]
If you start reading this way, you might be able to visualize the under the stones position. :)
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Everything with love. Stay safe.
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Re: Ekisei Tsubiho 1

Post by Splatted »

A little late, but my process for the first one:
My first instinct is to check if white can make eyes with the space available. It seems black has to ignore two moves in a row:
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . 4 2 . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O 5 X x O X a |
$$ . . X O X 3 1 y . b |
$$ ---------------------[/go]
Changing the order or playing "x" or "y" doesn't help. There's a possibility of getting the first move by playing "a" first and threatening a ko with 1 after black tackes at "b", but it's not enough. Still I wonder if there might be more to exploit there. I try reading things like this:
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X c X b . |
$$ , . X . . . , 1 X . |
$$ . . X O O O O O O X |
$$ . . X O . X . O X a |
$$ . . X O X . x y z . |
$$ ---------------------[/go]
Threatening a cut at "b" in the hopes of somehow extending the tesuji at "a" or breaking out with "c". I'm guessing dragon in the old Chinese naming for convention for problems is not related to the meaning of a long thin group extending in to the centre, but I can't help but think of that when I hear dragon.

Since none of that pans out I go back to looking at "x","y", and "z" in the hopes that I can find something to threaten on the left while also threatening "a". That's when I see it! The throw-in can be used on both sides! I think I've got it now, but just to be sure I'll read it out...
Click Here To Show Diagram Code
[go]$$Wc Black 6 at 1
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O . X . O X 1 |
$$ . . X O X 3 4 5 . 2 |
$$ ---------------------[/go]
... and it doesn't work. For some reason I thought black wouldn't have enough liberties to fill in at 3.

I'm tempted to give up and look at the answer here but since I'm tired I think I'll sleep on it and look again with fresh eyes.
The solution is... er... to be announced at a later date. :oops:
Last edited by Splatted on Wed Apr 15, 2020 1:17 pm, edited 2 times in total.
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Re: Ekisei Tsubiho 1

Post by Elom »

I'm still a bit behind on the First one, although I do get the feeling that capturing-stones-captured stones puzzles :).

It's interesting that this particular tsumego from china was a tsuhibo. Given that hints are often given Chinese names I wonder if assisted puzzles were more common in China than Japan during that time period (and maybe Japan later adopted it more?)
On Go proverbs:
"A fine Gotation is a diamond in the hand of a dan of wit and a pebble in the hand of a kyu" —Joseph Raux misquoted.
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Re: Ekisei Tsubiho 1

Post by Splatted »

Second attempt at the first problem. I think I've got it!

Process:
Second attempt after my previous failed one. I intended to start by checking the sequences I read before for mistakes, but I couldn't help thinking what if I threw in twice on the bottom right? Could I catch white before he connects everything up...?

Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X 6 |
$$ . . X O O O O O O X |
$$ . . X O . X . O X 1 |
$$ . . X O X . 5 4 3 2 |
$$ ---------------------[/go]
Alas I can only hope for the worthless :b4: before the rest connects. Still this is worth exploring more. What if I also throw in on the left and force black to loosely connect his groups?
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O . X . O X 1 |
$$ . . X O X 5 6 4 3 2 |
$$ ---------------------[/go]
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X a |
$$ . . X O O O O O O X |
$$ . . X O 1 X 3 O X 4 |
$$ . . X O X 2 X X 5 X |
$$ ---------------------[/go]
And I was going to say this would allow me to catch some stones, but it's a dead shape. However while making the diagram I realised that black has to respond to 5 at "a", so white can live as below.
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X 2 |
$$ . . X O O O O O O X |
$$ . . X O W . W O X X |
$$ . . X O . 3 . . 1 X |
$$ ---------------------[/go]
I think it might now just be a case of checking variations and ensuring all moves are optimal. I've already noticed that black should play :b2: before T2 and can take :w1: instead of connecting, but I don't think anything will change the result. I'm mainly trying to decide if the order of the two marked white stones matters and double checking all of blacks moves really are forcing moves.

This is my final process diagram.
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X 6 |
$$ . . X O O O O O O X |
$$ . . X O 7 X a O X 1 |
$$ . . X O X 5 b 4 3 2 |
$$ ---------------------[/go]
I thought there was potential for a ko if black ignored 5 and white played at 7 instead of "a", but I was still seeing a black stone at "b" and of course there wouldn't be if he didn't capture. I think my sequence is as good as it's going to get now, so time to post my solution! :D
Solution:
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O 7 X a O X 1 |
$$ . . X O X 5 6 4 3 2 |
$$ ---------------------[/go]
I chose :w7: over "a" because white then has the option of capturing a stone immediately and gaining a liberty if it becomes necessary later.
Click Here To Show Diagram Code
[go]$$Bcm8
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X 3 |
$$ . . X O O O O O O X |
$$ . . X O O X 2 O X . |
$$ . . X O X 1 X X 4 X |
$$ ---------------------[/go]
Click Here To Show Diagram Code
[go]$$Bcm12
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X X |
$$ . . X O O O O O O X |
$$ . . X O O . O O X . |
$$ . . X O . 2 . 1 . X |
$$ ---------------------[/go]
And there we have it. I'm a little dissappointed that I saw it while writing a diagram instead of relying purely on my reading, but I guess it's not a big deal.
Now I can finally check my answer! That really was a fun problem... but I don't think I'll move on to the next one immediately. :blackeye:

Edit: It seems I missed some important lines but I at least got the gist, which is a big improvement from the other day. I'm still reasonably content.

Edit 2: Haha since John described it as "not too hard" I assumed everyone who had posted hide tags had solved it quickly and easily in their heads. I would have given up sooner if I new dan players found it difficult! :lol:
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Re: Ekisei Tsubiho 1

Post by Elom »

My thinking so far--thank you for the diagram jlt!

My First written foray will focus on the many captures black can make . . .
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O . X 7 O X 1 |
$$ . . X O X 5 6 4 3 2 |
$$ ---------------------[/go]
This is what I foresee if black plays the 'non-thinking' response. Unless I'm badly mistaken, it doesn't seem that there's a way to stop white from gaining two eyes, so black maybe has a way to not make it so easy for white after 1.
On Go proverbs:
"A fine Gotation is a diamond in the hand of a dan of wit and a pebble in the hand of a kyu" —Joseph Raux misquoted.
RobertJasiek
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Re: Ekisei Tsubiho 1

Post by RobertJasiek »

Two moves have been suggested.
Click Here To Show Diagram Code
[go]$$W
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O 1 X . O X . |
$$ . . X O X . X X . X |
$$ ---------------------[/go]
Click Here To Show Diagram Code
[go]$$W
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O . X 1 O X . |
$$ . . X O X . X X . X |
$$ ---------------------[/go]
Studying the first:
Click Here To Show Diagram Code
[go]$$W
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O 1 X 2 O X . |
$$ . . X O X 3 X X . X |
$$ ---------------------[/go]
Studying the second:
Click Here To Show Diagram Code
[go]$$W
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O 2 X 1 O X . |
$$ . . X O X 3 X X . X |
$$ ---------------------[/go]
Click Here To Show Diagram Code
[go]$$W
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X 8 |
$$ . . X O O O O O O X |
$$ . . X O 4 . O O X . |
$$ . . X O . O 7 6 5 X |
$$ ---------------------[/go]
The first move results in a ko (if Black's reply turns out to be optimal), the second move results in death. Therefore, only the first move deserves further reading (starting with Black 2 at 3) to find out whether a better ko or status can be achieved.
Elom
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Re: Ekisei Tsubiho 1

Post by Elom »

Continuing from before . . .
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O . X 7 O X 1 |
$$ . . X O X 5 6 4 3 2 |
$$ ---------------------[/go]
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O 9 X O O X . |
$$ . . X O X 0 X X 8 X |
$$ ---------------------[/go]
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O O . O O X . |
$$ . . X O . . . . 1 X |
$$ ---------------------[/go]
Hmmm, am I missing something . . .
On Go proverbs:
"A fine Gotation is a diamond in the hand of a dan of wit and a pebble in the hand of a kyu" —Joseph Raux misquoted.
Elom
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Re: Ekisei Tsubiho 1

Post by Elom »

RobertJasiek wrote:Two moves have been suggested.
Click Here To Show Diagram Code
[go]$$W
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O 1 X . O X . |
$$ . . X O X . X X . X |
$$ ---------------------[/go]
Click Here To Show Diagram Code
[go]$$W
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O . X 1 O X . |
$$ . . X O X . X X . X |
$$ ---------------------[/go]
Studying the first:
Click Here To Show Diagram Code
[go]$$W
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O 1 X 2 O X . |
$$ . . X O X 3 X X . X |
$$ ---------------------[/go]
Studying the second:
Click Here To Show Diagram Code
[go]$$W
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O 2 X 1 O X . |
$$ . . X O X 3 X X . X |
$$ ---------------------[/go]
Click Here To Show Diagram Code
[go]$$W
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X 8 |
$$ . . X O O O O O O X |
$$ . . X O 4 . O O X . |
$$ . . X O . O 7 6 5 X |
$$ ---------------------[/go]
The first move results in a ko (if Black's reply turns out to be optimal), the second move results in death. Therefore, only the first move deserves further reading (starting with Black 2 at 3) to find out whether a better ko or status can be achieved.
Aah . . .
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O . X 7 O X 1 |
$$ . . X O X 5 6 4 3 2 |
$$ ---------------------[/go]
However:
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O 8 X 7 O X 1 |
$$ . . X O X 5 6 4 3 2 |
$$ ---------------------[/go]
So white needs to play at that point directly . . .
Click Here To Show Diagram Code
[go]$$Wc
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . . . . . . . . |
$$ . . . X . X . X . . |
$$ , . X . . . , . X . |
$$ . . X O O O O O O X |
$$ . . X O 7 X . O X 1 |
$$ . . X O X 5 6 4 3 2 |
$$ ---------------------[/go]
On Go proverbs:
"A fine Gotation is a diamond in the hand of a dan of wit and a pebble in the hand of a kyu" —Joseph Raux misquoted.
Elom
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Re: Ekisei Tsubiho 1

Post by Elom »

SoDesuNe wrote:
Click Here To Show Diagram Code
[go]$$Wc
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X . . , X O . .
$$ | . . . X . O . .
$$ | . X . O O . . .
$$ | . . . . . . . .
$$ +-----------------[/go]
Thoughts and attempt:
I also have difficulties with those "open border"/undefined eye-shape problems. I try to cope with this in two ways: First is starting not with vital points but with eye-space-reducing-moves and submissive replys (if they work I don't need to read complicated stuff). This is simple and can be calculated quite quickly. Second is following the proverb that your opponent's key point is your own.

Disclaimer: I did need a board and stones again, to figure out all the intricacies. Though I have to say, I got to the first four moves on my own and saw a good chunk of the variations.
Click Here To Show Diagram Code
[go]$$Wc Reducing Black's eye-space
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X . . , X O . .
$$ | . . . X . O . .
$$ | . X 1 O O . . .
$$ | . . . . . . . .
$$ +-----------------[/go]
Click Here To Show Diagram Code
[go]$$Wc Variation 1: Tearing through
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X . . , X O . .
$$ | . . 3 X . O . .
$$ | . X 1 O O . . .
$$ | . 2 . . . . . .
$$ +-----------------[/go]
Click Here To Show Diagram Code
[go]$$Wc Variation 2: Helping Black build a nice nest
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . 5 X X . O . .
$$ | X 6 . , X O . .
$$ | . . 2 X . O . .
$$ | 4 X 1 O O . . .
$$ | . 3 . . . . . .
$$ +-----------------[/go]
Now you can start going backward. Try :w5: at :b6: for example. It still lives (insert effortful practice ; )), so you have to go back even further.
Click Here To Show Diagram Code
[go]$$Wc Variation 3: where are Black's eyes?
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X . d a X O . .
$$ | b c 2 X . O . .
$$ | . X 1 O O . . .
$$ | . . . . . . . .
$$ +-----------------[/go]
It's time to go deeper now. Recognise the eye-shape, see familair patterns. After the exchange :w1: for :b2:, it is "easy" to see that 'a' is already an eye. The second eye will most likely be around 'b'. Do you have any moves to take away the second eye?

I reckon you will end up in situations where 'c' and 'd' become miai and so Black lives.

With all that out of the way: What did we learn?

1) We have an idea, where Black's eyes will be.
2) When Black responds at :b2: he's already alive.

So :b2: seems to be a key point in Black's shape. According to proverb this key point could also work in White's favour!
Click Here To Show Diagram Code
[go]$$Wc Variation 4: Cutting the eye!
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X . . . X O . .
$$ | . . 1 X . O . .
$$ | . X . O O . . .
$$ | . . . . . . . .
$$ +-----------------[/go]
Click Here To Show Diagram Code
[go]$$Wc Variation 4: tearing through the 2nd
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X . . . X O . .
$$ | . 2 1 X . O . .
$$ | . X 3 O O . . .
$$ | . . . . . . . .
$$ +-----------------[/go]
Click Here To Show Diagram Code
[go]$$Wc Variation 5: Entering the belly of the beast
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X b O . .
$$ | X . . . X O . .
$$ | . . 1 X a O . .
$$ | . X 2 O O . . .
$$ | . . . . . . . .
$$ +-----------------[/go]
This gets more complex but can also be made a little bit rational. White should not be so fast and play atari at 'a'. Black will sacrifice this stone and live - please confirm : )

Furthermore when Black cannot capture White with his next move, the atari can be played later as well. If Black plays 'a', White can force 'b' with the same result.
Click Here To Show Diagram Code
[go]$$Wc Variation 5
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X . . . X O . .
$$ | . 3 1 X . O . .
$$ | . X 2 O O . . .
$$ | . . . . . . . .
$$ +-----------------[/go]
So, when you have confirmed that :w3: is Black's key point to live when White decides to atari right away, why not play there yourself?
Click Here To Show Diagram Code
[go]$$Bcm4 Variation 5: No ko!
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X 4 O . .
$$ | X . 3 . X O . .
$$ | . O O X 2 O . .
$$ | 1 X X O O . . .
$$ | . . . . . . . .
$$ +-----------------[/go]
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[go]$$Bcm4 Variation 6: Black collapses due to liberty shortage
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X 8 . 3 X O . .
$$ | 6 O O X 2 O . .
$$ | 1 X X O O . . .
$$ | . 5 4 7 . . . .
$$ +-----------------[/go]
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[go]$$Bcm4 Variation 7: Ko
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X . 3 4 X O . .
$$ | 1 O O X 2 O . .
$$ | . X X O O . . .
$$ | . . . . . . . .
$$ +-----------------[/go]
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[go]$$Bcm4 Variation 8: If Black refuses the ko...
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X 8 . 3 X O . .
$$ | 1 O O X 2 O . .
$$ | 6 X X O O . . .
$$ | . 5 4 7 . . . .
$$ +-----------------[/go]
But did you remember the proverb? Your opponent's key-point is your own?
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[go]$$Bcm4 Variation 9: Guzumi!
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X . . . X O . .
$$ | . O O X . O . .
$$ | . X X O O . . .
$$ | . . 1 . . . . .
$$ +-----------------[/go]
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[go]$$Bcm4 Variation 9: Or not...
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X 4 . . X O . .
$$ | 3 O O X . O . .
$$ | 2 X X O O . . .
$$ | . . 1 . . . . .
$$ +-----------------[/go]
So, I guess it's ko?

To be fair, this ko is better for Black:
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[go]$$Bcm4 Variation 10: Ko²
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X . 1 3 X O . .
$$ | . O O X 2 O . .
$$ | 6 X X O O . . .
$$ | 7 4 5 . . . . .
$$ +-----------------[/go]
(I'm really tired now, so the possibilitiy is high that I missed something ^^)
TL;DR
Start with reducing the eye-space. Play the move, which refuted your last play.
Thank you for your notes!

I recently finished a game in which I thought I'd lost a few points the endgame. Having already estimated being behind by just under komi, it seemed that there wasn't anywhere to catch up, however, an ai analysis believed that black had only about .64 of a victory, and that before the slip I was actually a little ahead. Perhaps it was the amount of unclear endgame positions that seemed a bit above me to play correctly that influenced over-pessimism--that and that it looked too good to mess up with my bad moves!

So I came up with a strategy for satisfyingly finishing endgames that look too good to misplay, which also happens to seem to help here where the stones are spread out in a way that makes it hard to have a solving strategy . . .
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[go]$$Wc vital points with no expectation
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X b a , X O . .
$$ | . . . X . O . .
$$ | . X . O O . . .
$$ | . . . . . . . .
$$ +-----------------[/go]
As most, I started by looking for vital points, but with no expectation--the goal was to first acquire a feel for the position by painting with intuition, starting of with it seeming that an attempt at a could be halted immediately at b.
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[go]$$Wc vital points with no expectation 2
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X . 4 5 X O . .
$$ | . 3 1 X 5 O . .
$$ | . X 2 O O . . .
$$ | . . . . . . . .
$$ +-----------------[/go]
Black seems to have an advantage here . . . But I may have missed something!
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[go]$$Wc an idea
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | . . X X . O . .
$$ | X . . , X O . .
$$ | . 1 . X . O . .
$$ | . X . O O . . .
$$ | . . . . . . . .
$$ +-----------------[/go]
This was the point that gave me the idea for the next move. It doesn't appear to work--black respond at B4 poor C3, as both seem to give C2 and then C1 to squeeze away black's second eye. But if black responds at C1 it seems like it stays alive . . . However!
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[go]$$Wc Cool clamp
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ | . O O O O . . .
$$ | 8 6 X X . O . .
$$ | X 5 . , X O . .
$$ | 7 . 2 X . O . .
$$ | 3 X 1 O O . . .
$$ | . 4 . . . . . .
$$ +-----------------[/go]
It often feels satisfying to play a clamp, as if one was saying to the opponent you think I have to hane, well see this. Similar to playing one's own way in the fuseki. I don't see a response yet for black that works . . .

edit: checked the answer, and yes this is the start of the given variation.
On Go proverbs:
"A fine Gotation is a diamond in the hand of a dan of wit and a pebble in the hand of a kyu" —Joseph Raux misquoted.
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