Occurred in my last game. White resigned instead of playing the circled move. In the game I thought the white move would save the group. Not sure if my opponent read it out, or didn't even think of the move. Relatively easy if you look at it as a tsumego, but I think I might have missed it ingame.
$$ Black to move and kill
$$ . . . . . . . . . . . .
$$ . . , . . O O X X X . .
$$ . . . O O . X O O X . .
$$ . . . O X X X . O X . .
$$ . . . X O X O . O X . .
$$ . . . . . . O . O X . .
$$ . . . X . X X O O X . .
$$ . . X . . O . O X X . .
$$ . . X O O X X O X . . .
$$ . . . X X O O O X . . .
$$ . . . . . O . X . . . .
$$ - - - - - - - - - - - -
[go]$$ Black to move and kill
$$ . . . . . . . . . . . .
$$ . . , . . O O X X X . .
$$ . . . O O . X O O X . .
$$ . . . O X X X . O X . .
$$ . . . X O X O . O X . .
$$ . . . . . . O . O X . .
$$ . . . X . X X O O X . .
$$ . . X . . O . O X X . .
$$ . . X O O X X O X . . .
$$ . . . X X O O O X . . .
$$ . . . . . O . X . . . .
$$ - - - - - - - - - - - -[/go]
Last edited by Li Kao on Mon Mar 07, 2011 9:03 am, edited 2 times in total.
$$ Black to move and kill
$$ . . . . . . . . . . . .
$$ . . , . . O O X X X . .
$$ . . . O O . X O O X . .
$$ . . . O X X X . O X . .
$$ . . . X O X O a O X . .
$$ . . . . . 1 O . O X . .
$$ . . . X . X X O O X . .
$$ . . X . b O . O X X . .
$$ . . X O O X X O X . . .
$$ . . . X X O O O X . . .
$$ . . . . . O . X . . . .
$$ - - - - - - - - - - - -
[go]$$ Black to move and kill
$$ . . . . . . . . . . . .
$$ . . , . . O O X X X . .
$$ . . . O O . X O O X . .
$$ . . . O X X X . O X . .
$$ . . . X O X O a O X . .
$$ . . . . . 1 O . O X . .
$$ . . . X . X X O O X . .
$$ . . X . b O . O X X . .
$$ . . X O O X X O X . . .
$$ . . . X X O O O X . . .
$$ . . . . . O . X . . . .
$$ - - - - - - - - - - - -[/go]
"The more we think we know about
The greater the unknown" Words by neil peart, music by geddy lee and alex lifeson
$$ Black to move and kill
$$ . . . . . . . . . . . .
$$ . . , . . O O X X X . .
$$ . . . O O . X O O X . .
$$ . . . O X X X . O X . .
$$ . . . X O X O . O X . .
$$ . . . 4 2 3 O . O X . .
$$ . . . X . X X O O X . .
$$ . . X . 1 O . O X X . .
$$ . . X O O X X O X . . .
$$ . . . X X O O O X . . .
$$ . . . . . O . X . . . .
$$ - - - - - - - - - - - -
[go]$$ Black to move and kill
$$ . . . . . . . . . . . .
$$ . . , . . O O X X X . .
$$ . . . O O . X O O X . .
$$ . . . O X X X . O X . .
$$ . . . X O X O . O X . .
$$ . . . 4 2 3 O . O X . .
$$ . . . X . X X O O X . .
$$ . . X . 1 O . O X X . .
$$ . . X O O X X O X . . .
$$ . . . X X O O O X . . .
$$ . . . . . O . X . . . .
$$ - - - - - - - - - - - -[/go]
I could only think of this, not sure why I never considered trying my third move as a first move.
It still dies, but white gets away slightly.