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White pushes into Black's upper left corner first.

For further details of our earlier analysis, please refer to the history of our investigations ...
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Black must connect.

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White prevents her group at the left from being captured.

Inserting the second push into the upper left corner with , , instead, will not affect the outcome of the ensuing sequence.

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Black captures White's single stone in the right centre immediately.
This timing is favoured with small reverse komi.

With a large reverse komi, KataGo wants to insert the kikashi of , before, and continue with the Nakade Sequence thereafter.

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Black's throw-in creates a false eye in White's formation, so gaining one additional liberty in the forthcoming semeai.

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Black attacks from the right first, also creating another false eye for White's group.

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White has to connect.

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Thereafter, Black reduces White's eye space from the left.

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Black played from the right first (with ), so White's peep at the upper edge - which is sente - is favoured by KataGo, resulting in White's success.

Please note that this peep was the move that KataGo searched for so long in its initial 2019 training.

Runner-up in KataGo's assessment is Joachim's immediate connection at the left.
This alternative option would result in a genuine version of Joachim's Ko-Semeai.

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KataGo inserts this kikashi, ...

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... before playing the mandatory connection at the upper edge.

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Now, White closes to borders of her two-point eye at the top.

Had White played this connection first (as mentioned above), both KataGo's peep and also the bump chosen by Joachim would later be valid options.

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KataGo intends to create a ko-shape in the right centre.

KataGo did not create the ko-shape at the right, starting with , what Joachim did first in his Ko-Semeai.

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White reduces the size of Black's eye.

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White destroys Black's potential second eye in the right centre.

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Black's descent to the upper edge starts the mutual occupation of opponent's liberties in the semeai.

Playing at , creating another ko-shape at the right, would not benefit Black either.

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White's oki is mandatory.

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Black continues with the mutual occupation of opponent's liberties.

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White has to start filling her false eyes in due time.

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Black solidifies his upper left corner, erasing several potential White ko-threats in this area.

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Black prepares "quick" ko-threats in the Nakade Area.

Ko:

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White starts the ko-fight in the centre.

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Black gives atari at White's centre group.

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White recaptures the ko, giving atari at Black's large group in the upper right.

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Black gives atari at White's four stones at the left, well knowing that White will be unable to answer locally.

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White must capture Black's group at the right, so ending the ko-fight.

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Black captures White's four stones, so killing her group at the left.

Black connected the hanezeki's tail and killed the entire left side, but White killed the entire right side in return, which is bigger.

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White might continue with the endgame in the lower left corner.

Please note that Black is unable to attack White's remaining hanezeki group in the lower right corner with , as long as he has not reduced White's already captured group at the left to only one liberty.

Compared to the "usual" Semeai Variation, wherein Black also captured White's corner group, the territorial swing in the lower right corner is about 45 points in White's favour.

White will win the game by a large margin.

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