Xuanxuan Qijing Problem 239 / Solution

Solution  

After !, the best Black can get is a one-move approach ko.

Cont. 1  

is the move that links the black stones together to create connect and die situation.

Cont. 2  

is important. Black needs another move at a to make it a direct ko. See Failure below for what happens when is at .

Failure  

is an unexpected good move.

Cont.  

After recaptures, the white group dies.