In this game I do not understand why black played h3 with his move 99 instead of j6. He would have been able to sperate white into 2 weak groups. Can somebody show/explain why he didn't play j6 and instead kept white connected?

Maybe black wants to kill all? She probably did not consider the bad aji at G11 serious enough. If J6 instead of H3, white G3 just gives enough room to make two eyes. Please confirm.

Black apparently wanted to kill the whole dragon instead of just cutting off its tail. If black plays the cut he might swallow the three stones in the middle but white gets to live comfortably on the bottom with some points. Now, whether black went for the kill because he felt just killing the tail wasn't enough, because he was confident it would all die or because he thought this way was more fun is hard to tell. In any case you can see that he came pretty close to killing it all!

EDIT: or "she"?

You guys are probably right. The move at h3 makes the most sense if one assumes black wanted to kill the whole white thing. But that was reckless, because h3 lets white connect everything with j6 and then it looks more like white has better leverage to kill black's centre group than vice versa (which also was the case by the way). Oh, well, good to know that even pro's once in a while are caught up with being "too greedy"^^.

Both players are she

Best wishes.

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