: ( 648qv)
White pushes from above.

Occupying another liberty of Black's group, e.g. with , would result in a change in the order of moves.

:
Black must connect his two partial groups, simultaneously capturing White's single stone below.

Black is able to play this move after any White move before.

Black plays 1/1 reduction.

Capture Variation:

Compared to the superordinate variation ...

• Black captured one White stone in the upper right, so gaining two points.

White lost two points.

White + 1 => Black + 1

Semeai Variation:

Compared to the superordinate variation ...

• White lost one point of territory in the upper right corner.
• White gained one point of territory in the upper right centre.

In total, gains and losses compensate for each other.

Black + 1 => Black + 1