: ( 648mk)
Black connects in the centre.

: ( A 648mt; B 648mx)
White connects at the upper edge, but which is not correct here.

As we now know, White has to play her kikashi in the lower left corner first.

Blocking at at the top, instead, will be also mistaken.

: (A 648my)
Black continues with the ko fight.

After White's mistake above, simplifying the issue by pushing at at the top, not intending to fight the ko in the centre any longer, will be a succeeding mistake, and one point worse overall.

Ko: ; ; ; ; ;

:
Black's push at the top is no absolute sente.

:
This is the last moment, when White could (and should) play her kikashi at in the lower left corner successfully. Please refer to the respective subvariation above for the detailed continuation.

If White played this move later, as an additional ko threat, Black will ignore it and connect the ko in the centre. White would lose two points overall (compared to the correct line of play above).

Ko: ; ; ; ;

; :
Please understand these two moves as replacement for White's kikashi , in the centre, which had been played too early by us.

We now know that this atari cannot be counted as an additional ko threat.
Here, in this subvariation, however, our earlier mistake does not really matter, as White will win the ko fight in the left centre anyway; see below.

; ; ; :
These ko threats cost one tempo in the Main Semeai each. Eventually, Black is one over par.

Please note that we did not update the board's border colour during this ko sequence.

:
Black continues with the Main Semeai by defending his territory in the lower left corner.

White is comfortably ahead in ko threats (3 x vs. ).

:
White is able to connect the ko "early".

Alternatively, she could continue with the Main Semeai, achieving the same final scores.

Black is unable to capture at , and to connect thereafter, because he is too close to the Punishment Semeai Liberty Level.

Black plays 0/1 reduction.

Capture Variation:

Compared to the superordinate variation ...

• Black got two additional points of territory in the lower left corner.
• Black did not destroy one point of White's territory at the top.

In total, Black gained one point.

White + 2 => White + 1

Semeai Variation:

Compared to the superordinate variation ...

• Black got two additional points of territory in the lower left corner.
• White captured one Black stone less at the upper edge, so losing one point.
• Black captured one White stone less in the lower left corner, so losing two points.

In total, Black gained one point.

White + 2 => White + 1