Beginner Exercise 172 / Solution

White dies from a lack of creativity.  

A tesuji is required, eh? Well, the simplistic move at obviously doesn't work, maybe I'll sacrifice something...

White lives, but can black put up a better fight?  

This is not black's best resistance - the kill still works.

Black has a foil!  

Yep, black can do this. at a doesn't prevent either. White cannot engage in self-indulgent reading! Playing immediately at doesn't work either - black has enough liberties to push at and falsify the other eye.

Easier to refute... Or is it?  

Capturing the marked stone doesn't get an eye. But wait, why not at ?

Black can't kill the other eye.  

Black can't play at a because of a shortage of liberties created by . An approach move at b or c is required first, which gives white enough time to play a. at a obviously doesn't work (white captures saving the eye), nor does b, which makes a sente for white. at c has the same result as this diagram. Playing at d is easily refuted by at making for two real eyes on the bottom. There are a couple large ko threats left here for black; at d would prevent one at the cost of one point.