: ( 648ab)
White plays Dany's atekomi, intending to start Dany's Ko a few moves later.

Please note that this move is played outside the Main Semeai, but does not lose a tempo therein, because becomes an approach-move liberty of White's group at the left.

Black is still par with the Punishment Semeai Liberty Level.

Black is unable to continue with , or , in the left centre, because any of these moves would push him below the Punishment Semeai Liberty Level.
On the other hand, White threatens the severe cut at , which would win her the game.

: (C 648cy)

Black is strictly bound to continue with the Main Semeai. Therefore, giving atari at is his only choice on the left side of the board, because this move is the only one that also defends against White's cut at (which White will not play now; please refer to this subvariation 648of for details).

Alternatively, Black might consider playing his kikashi in the hanezeki first, in order to prevent White's following move at this point.

However, as we now know, the corresponding loss of a potential ko threat will have a decisive effect on Dany's ko, which is to come in the left centre.
White would win the ko fight without having to resort to any disadvantageous ko threat, so gaining one point in both Main Variations.
It would be preferable for Black to let White choose the following subvariation, where Black would at least win the Capture Variation.

: ( C 648db)
White connects at , providing Black with two Main Semeai Liberties. Thereafter, Black will be able to defend against White's cut at .

However, as we now know, it will be better for White to ignore Black's atari in the lower left, and to prevent Black's kikashi in the hanezeki by playing at the point of lC herself. White will gain one point overall.

We ask for your kind understanding that we felt unable to adjust the move numbers (i.e. to increase these by two) in the many already created diagrams, which follow in this part of the variation tree.

: (A 648ds)
Black plays atari, initiating Dany's Ko.

Black will lose the following ko fight, so he might consider simplifying the issue by retreating to .

However, this move would be played too early, losing one point overall.
As we now know, there are very sensible interdependencies between the reduction of the top, and the lower left corner, and the respective amount of ko threats, to consider.

: (A 648dv)
The ko fight begins.

Connecting at , instead, will simplify the matter, while not affecting the final scores of the game.

: (B 648ea)
White captures the nakade as a ko threat.

It might be tempting to play her gote move in the hanezeki, instead, stopping Black from playing his kikashi at that point. However, this alternative choice will end in a disaster for White.

Ko: ;

: (134 648eb)
White connects at the left edge.

She might consider splitting the Nakade Sequence for immediately capturing the ko - hoping for an additional ko threat, while following Dany's suggestion - but she will not benefit from this idea.
If she ever wanted to implement it consistently, she would no longer be able to win the game.

: (141 648ep)
Black uses his kikashi in the hanezeki as an additional ko threat.

He might also immediately play the safety-first connection at , achieving the same final scores.

: (141 648eq)
White answers Black's kikashi locally.

She must not try to take advantage by giving atari at , instead, intending to make the ko a fight for the life and death of Black's large group at the left.

: (B 648er)
Black has to connect his two stones - sooner or later.

We now know, that Black can make the matter much clearer by playing his push at (at least; may be his kikashi in the hanezeki, too) as a ko threat before the connection at the left edge.

This connection at the left edge, erasing Black's shortage of liberties in that area, was played by us "early" (in order to simplify the presentation) at a time, when we were sure that White would win the ko, even after her connection at at the upper edge - which would then be one point better overall than the block - in conjunction with her kikashi at in the lower left corner.
However, this is no longer true, as we now know. And in this case, blocking with at the top (with White winning Dany's Ko) is better for White than connecting her single stone at the upper edge with (with Black winning Dany's Ko), at least in the Semeai Variation.

: (C 648eu; A 648ev)
White plays her kikashi in the lower left corner.
Please note that this move loses one tempo in the Main Semeai.

Immediately connecting the ko with would be mistaken, as White would no longer be able to win the Semeai Variation.
However, White might alternatively consider connecting her single stone at the top with immediately. Not playing her kikashi in the lower left beforehand would gain her another ko threat at the lower left edge, allowing her to win the ko fight in the left centre again. Nevertheless, she will be unable to increase her scores.

: (145 648ew)
White blocks at the upper side.

White would gain territorially by connecting her single stone at the upper edge, instead.
However, this connection would provide Black with an additional ko threat in this area, enabling him to win the ko fight in the left centre, also compensating for his territorial loss at the upper edge. White would no longer be able to win the Semeai Variation.

If White ever wanted to connect at the upper edge, instead of blocking at the top, she should have done without her kikashi in the lower left corner, as can be seen in a subvariation above ( 648er).

: (150 648ez)
Black simplifies the issue by connecting at "early".

He will achieve the same final scores by further fighting the ko in the centre, but which he will lose.

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

Otherwise, Black will capture at due time, and connect, so gaining decisively.

:
Black connects the other ko at the upper edge.

Black plays 3/3 reductions.

Please assume Black's second kikashi in the hanezeki (, ) played before.

White will play her kikashi , in the lower left corner later in the game, so Black has to capture at there, due to his shortage of liberties above.

Capture Variation:

Compared to the superordinate variation ...

• White gained one additional point of territory by blocking at the top.
• Black did not get an eye in the left centre, so losing one point.
• Black destroyed three points of White territory at the right.

In total, White lost one point.

White + 2 => White + 1

Semeai Variation:

Compared to the superordinate variation ...

• White gained one additional point of territory by blocking at the top.
• Black did not get an eye in the left centre, so losing one point.
• White captured an additional two Black stones at the left, so gaining three points.

In total, White gained five points.

Black + 4 => White + 1