I played a game against Lord Spoon who attends my Twitch channel. It was a good correspondence game with several places where each side could’ve played a single decisive stone to wreck an opponent group.
If you can recognize the brutal play in each of these situations, you will be much further ahead in your go career:
The most wicked is first: Move 47, Say Good Night
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Move 122, Black to Play
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Move 75 White to Play
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I’m going to give a hint here. Even though P14 is the strongest move, I’m more interested in the L&D situation at the bottom… particularly given that the knee-jerk move M3 is what you might play reflexively without thinking deeper.