(Referenced by 649au)

: ( 649ag)
Black solidly connects his troops at the left side of the board.

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White's kikashi in the lower left corner is absolute sente, threatening to kill Black's left-hand group.

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White's wedge in the right centre makes the difference in the Semeai Variation.

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Black's push at the top is sente.

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Eventually, Black has to immobilise White's stone below.

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White connects at the upper edge.

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The Main Semeai continues.

Black plays 3/3 reductions.

Before the end of the game, Black will have to capture at in the lower left corner.

Capture Variation:

Compared to the superordinate variation ...

• Black destroyed one point of White's territory in the upper right corner.
• White destroyed one point of Black's territory in the rifth centre.

In total, gains and losses compensate for each other.

White + 2 => White + 2

Semeai Variation:

Compared to the superordinate variation ...

• White captured an additional Black stone in the upper right corner, so gaining one point.
• White captured one Black stone less in the right centre, but lost two points of territory there, so the net effect is zero.

In total, Black lost one point.

White + 1 => White + 2

This was the "standard" result of the Semeai Variation of Dany's Ko at the time when we mistakenly used White's wedge in the right centre as a ko threat.