(Referenced by 648cx)

: ( 648cx)
Black plays his push at the top.

: (A 648es)
Black's ko threat is no absolute sente, but here, White will not insert her kikashi at in the lower left corner.

If she did, she would no longer be able to win the Semeai Variation.

Ko: ; ;

:
The ko fight continues.

:
Black has to erase his shortage of liberties at the left.

:
White connects her single stone at the upper edge.

:
White is barely ahead in ko threats (6 x vs. 5 x ), so Black simplifies the issue by continuing with the Main Semeai.

:
White has to connect the ko - sooner or later.

Black plays 2/3 reductions.

Capture Variation:

Compared to the superordinate variation ...

• White's cumulated gain at the upper edge is two points.
• Black destroyed an additional point of White's territory at the top.
• Black's cumulated gain in the lower left corner is two points.
• Black did not destroy one point of White's territory in the upper right corner.

In total, gains and losses compensate for each other.

White + 1 => White + 1

Semeai Variation:

Compared to the superordinate variation ...

• White's cumulated gain at the upper edge is two points.
• Black destroyed an additional point of White's territory at the top.
• Black's cumulated gain in the lower left corner is two points.
• White captured one Black stone less in the upper right, so losing one point.
• Black captured one White stone less in the lower left corner, so losing two points.

In total, gains and losses compensate for each other.

White + 1 => White + 1