Bulky Ten In The Corner

Bulky ten in the corner  

Black can play at any of the 7 marked intersections to live outright with 9 points of territory, but is best because it leaves either no ko threats or only one tiny one (depending on the rules). ​ White-to-move plays .

start of main lines

is elsewhere  

is at k or s. ​ (Note that White has already taken gote.)

Seki

can be at either of the indicated points  

Reminder: ​ Although _the indicated sequence_ is sente, White took gote to get to the start of this diagram.

mannen-ko

 

Either player can make seki, or throw in for a ko that favors Black.

slightly-safe Ko

is a big ko threat  

If White ignores Black's ko threat, then White plays at , which kills Black. ​ If is still empty then after Black retakes the ko, Black's followup is capturing to live with 9 points under territory scoring. ​ If White retakes the ko, then Black can back down from it with . ​ (If Black would do that without having played a ko threat, then Black should not play this line.)

after Black backs down

direct ko for seki  

After Black backs down, the ko's swing becomes 9 points under territory scoring. ​ White wins it with for a seki in which White captured 1 net Black stone. ​ After , Black wins it by playing either of the other 2 marked points.

Black takes gote for points

Seki  

prevents a mannen-ko.