: ( 222cf)
Black pushes at the top.

:
White connects to the left, preventing a Black atari at the same point.

:
Black captures.

: ( 127 222ch)
White secures an eye at the top, also continuing with the Main Semeai.

It seems that KataGo likes to insert the kikashi of , in the upper left corner just now.
It will result the same final score of the game as in the best lines below.

: (125 222co ; B 222cv)
Black wants to get an optimal position for a threatening Central Semeai, and so throws-in in the right centre immediately.
Please note that KataGo usually does not want to play this throw-in.

Black might want to keep this kikashi in reserve and to give the immediate bump at the top a try.

As an alternative option, we also investigate what will happen after Black created an eye in the right centre first, with playing at .

:
Black's protective move at the top makes it impossible for White to win the Central Semeai on its own.

: (128 222cw ; 127 222cx ; C 222cy)
White returns to the upper left corner, occupying the outside liberty of Black's cut-off stones.

Alternatively, she might consider connecting at the left edge with , or extending at the upper edge with . The final scores of these subvariations will be the same as with the correct line of play below.

Immediately connecting at the top, however, would be too early here, and so a mistake that loses some points.

:
Black gives atari in the upper left corner.

There is no need to break through at the top with , instead.

: (C 222cz)
White connects at the left edge, preparing for the ko fight to come.

As two moves earlier, White's immediate connection at will also win the game, but still lose a few points unnecessarily.

: (A 222db)
Black starts the ko fight in the upper left corner.

He must not cut through at the top, instead.

:
White connects at the top.

Please note that White must not occupy Black's liberty at , instead.
Black would first secure an eye for his group with , and connect at again as early as possible in the course of the ensuing ko fight - if White had started any unnecessarily - ignoring most of her ko threats at the right. Thereafter, Black would win the Central Semeai.

: ( 132 222dc)
Black connects the ko, so turning the upper left corner into a seki.

However, continuing the ko fight for a few moves will benefit him by one point.

I found this improvement when studying one of the subvariations above ( 222cw) that contains a change in the order of moves for reaching this position.

:
White continues with the Main Semeai.

...

:
White must start the endgame on the left side of the board "early".

:
Black connects at the upper edge, simplifying the issue.

Alternatively, he might consider connecting at at the bottom, not affecting the outcome of the game.
Thereafter, White would descend to (or give atari at ), and Black would be unable to connect his hasami-stuke stone, in order not to fall below the Punishment Semeai Liberty Level.

Black must not play any reduction.

White will capture at after her decision point, and connect the ko thereafter.

Capture Variation:

Compared to the super²ordinate variation ...

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

In total, White gained one point.

White + 6 => White + 7