: ( 648cx)
White recaptures Dany's Ko, instead of finishing the Nakade Sequence.

: (A 648ec)
Black erases his shortage of liberties at the left edge immediately.

He must not continue with the ko fight, e.g. by playing his kikashi in the hanezeki as a ko threat. Unnecessarily, he would fall into the trap that White had set up with her splitting of the Nakade Sequence.

: (A 648ed)
White terminates the Nakade Sequence. This reverts to the superordinate variation.

However, in order to justify her splitting the Nakade Sequence, White would have to deviate from the "usual" continuation. She might want to play at , thereafter prioritising the Semeai Variation.

Now that we know that winning the ko is within Black's grasp, we need to be careful about the order of moves.

White wants to connect her single stone at the upper edge with , because this move gains the most territory outside the Main Semeai area. Black would be able to recapture the ko in the left centre with .

Thereafter, White is barely ahead in ko threats (8 x , vs. 8 x ), so she will win Dany's Ko.

This implies that she does not want to insert her kikashi , in the lower left corner (for gaining an additional point overall there), just because this would lose her ko threat at , resulting in Black winning Dany's Ko (and an overcompensation of his loss in the lower left).

Black might want to simplify the issue by not fighting the ko until the very end.

White's second option at the top is the block with .

In this case, White is comfortably ahead in ko threats (7 x , vs. 4 x , ). A loss of her ko threat at would not affect the outcome of the ko fight.

Black will capture White's single stone at the upper edge in return. Now, it is Black, who gains territorially at the top.
White will insert her kikashi , in the lower left corner (gaining an additional point overall there, which compensates for her loss at the top), before blocking with at the upper edge.
Black might recapture Dany's Ko with , of simplify the issue by continuing with the Main Semeai. In neither case, he will use his last, but disadvantageous, ko threat at in the upper right, which loses one point overall.

White might also consider changing the order of moves, and start with her kikashi , in the lower left corner.
In this case, blocking with at the top is her only move.

: (137 648em)
We will follow White's second option here, and let her block at the top. The continuation corresponds to the description above.

Alternatively, she can connect her single stone at the top with .

(141 648eo)
White defends her territory at the upper edge.

She might consider pre-empting Black's following kikashi in the hanezeki by taking the point of herself.
However, she will be unable to get a better result than here.

; :
Black knows that the will be unable to win Dany's Ko, and so plays his remaining kikashi in the hanezeki.

:
Thereafter, he continues with the Main Semeai.

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

:
Black connects the other ko at the upper edge.

We have reached a change in the order of moves with the superordinate variation.

White will win both Main Variations by one point