From a 9x9-game I played on OGS against a 1d. Looks like a standard shape (and maybe there is a standard answer), but I had to resort to non-standard solutions (well, for my (3k) standard of standard ;). I found it highly instructive and enjoyable. You might too:
White to live:
$$W
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$$ | . . . . . . O . . |
$$ | . . . X . X O . B |
$$ | . . . . X . . . . |
$$ | . . . . . X O . O |
$$ | . . . . X . O O X |
$$ | . . . . X O O X . |
$$ | . . . X . X X . X |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ ----------------------
[go]$$Wc Double-Ko? 1
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$$ | . . . . . . O . 5 |
$$ | . . . X . X O 3 B |
$$ | . . . . X . . 1 2 |
$$ | . . . . . X O 4 O |
$$ | . . . . X . O O X |
$$ | . . . . X O O X . |
$$ | . . . X . X X . X |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ ----------------------[/go]
$$Bc Double-Ko? 2
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$$ | . . . . . . O 1 O |
$$ | . . . X . X O O X |
$$ | . . . . X . . O X |
$$ | . . . . . X O X 2 |
$$ | . . . . X . O O X |
$$ | . . . . X O O X . |
$$ | . . . X . X X . X |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ ----------------------
[go]$$Bc Double-Ko? 2
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$$ | . . . . . . O 1 O |
$$ | . . . X . X O O X |
$$ | . . . . X . . O X |
$$ | . . . . . X O X 2 |
$$ | . . . . X . O O X |
$$ | . . . . X O O X . |
$$ | . . . X . X X . X |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ ----------------------[/go]
or...
$$Wc Simple Ko?
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$$ | . . . . . . O . . |
$$ | . . . X . X O . B |
$$ | . . . . X . 4 1 3 |
$$ | . . . . . X O . O |
$$ | . . . . X . O O X |
$$ | . . . . X O O X 2 |
$$ | . . . X . X X . X |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ ----------------------
[go]$$Wc The obvious Ko? 2
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$$ | . . . . . . O . . |
$$ | . . . X . X O . X |
$$ | . . . . X . O X . |
$$ | . . . . . X O . O |
$$ | . . . . X . O O 4 |
$$ | . . . . X O O X 7 |
$$ | . . . X . X X 5 X |
$$ | . . . . . . . 6 . |
$$ | . . . . . . . . . |
$$ ----------------------[/go]
$$Wc The obvious Ko? 3
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$$ | . . . . . . O . . |
$$ | . . . X . X O 9 X |
$$ | . . . . X . O X . |
$$ | . . . . . X O . O |
$$ | . . . . X . O O 0 |
$$ | . . . . X O O X O |
$$ | . . . X . X X 8 X |
$$ | . . . . . . . X . |
$$ | . . . . . . . . . |
$$ ----------------------
[go]$$Wc The obvious Ko? 3
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$$ | . . . . . . O . . |
$$ | . . . X . X O 9 X |
$$ | . . . . X . O X . |
$$ | . . . . . X O . O |
$$ | . . . . X . O O 0 |
$$ | . . . . X O O X O |
$$ | . . . X . X X 8 X |
$$ | . . . . . . . X . |
$$ | . . . . . . . . . |
$$ ----------------------[/go]
$$Wcm11 The obvious Ko? 4
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$$ | . . . . . . O . . |
$$ | . . . X . X O O X |
$$ | . . . . X . O X . |
$$ | . . . . . X O 1 O |
$$ | . . . . X . O O X |
$$ | . . . . X O O X . |
$$ | . . . X . X X X X |
$$ | . . . . . . . X . |
$$ | . . . . . . . . . |
$$ ----------------------
[go]$$Wcm11 The obvious Ko? 4
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$$ | . . . . . . O . . |
$$ | . . . X . X O O X |
$$ | . . . . X . O X . |
$$ | . . . . . X O 1 O |
$$ | . . . . X . O O X |
$$ | . . . . X O O X . |
$$ | . . . X . X X X X |
$$ | . . . . . . . X . |
$$ | . . . . . . . . . |
$$ ----------------------[/go]
for all: You can assume that black has a fair amount of external ko threads.
sodesune:
your first answer:
I agree with a lot of what you say. But in the last diagram, white has a better 3, although there is a lot of damage. And anyway, white has a better 1.
your second answer:
I don't agree with your 1. Ko was no option.
If something sank it might be a treasure. And 2kyu advice is not necessarily Dan repertoire..
$$Wc No ko
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$$ | . . . . . . O . . |
$$ | . . . X . X O 3 B |
$$ | . . . . X . . 1 . |
$$ | . . . . . X O . O |
$$ | . . . . X . O O X |
$$ | . . . . X O O X 2 |
$$ | . . . X . X X . X |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ ----------------------
[go]$$Wc No ko
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$$ | . . . . . . O . . |
$$ | . . . X . X O 3 B |
$$ | . . . . X . . 1 . |
$$ | . . . . . X O . O |
$$ | . . . . X . O O X |
$$ | . . . . X O O X 2 |
$$ | . . . X . X X . X |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ ----------------------[/go]
Another variation for b to capture some stones, but I think white lives.
$$Wc
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$$ | . . . . . . O . . |
$$ | . . . X . X O 2 B |
$$ | . . . . X . 4 1 3 |
$$ | . . . . . X O . O |
$$ | . . . . X . O O X |
$$ | . . . . X O O X 5 |
$$ | . . . X . X X . X |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ ----------------------
Well, I only added the Ko because I thought White could win it anyway. Your "[...] black has a fair amount of external ko threads" makes it clearer, thanks.
$$Wc Black komaster, White to live
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$$ | . . . . . . O . 2 |
$$ | . . . X . X O 1 X |
$$ | . . . . X . . . . |
$$ | . . . . . X O . O |
$$ | . . . . X . O O X |
$$ | . . . . X O O X . |
$$ | . . . X . X X . X |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ ----------------------
[go]$$Wc Black komaster, White to live
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$$ | . . . . . . O . 2 |
$$ | . . . X . X O 1 X |
$$ | . . . . X . . . . |
$$ | . . . . . X O . O |
$$ | . . . . X . O O X |
$$ | . . . . X O O X . |
$$ | . . . X . X X . X |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ ----------------------[/go]
Where next?
The Adkins Principle: At some point, doesn't thinking have to go on?
— Winona Adkins