Tsumego From Games 141 / Attempts

Main line (submitted by unkx80)  

Black may try a, b or c.

(It turns out that is necessary for White to live!)

unkx80: Huh, my reading is not so complicated, should not be needed.

Black a

Black at a ( = )  

Black may try i, j, or k.

Black at a, continued at i  

The ladder at x is broken by .

Black at a, continued at k  

Three liberties to two, White wins by one. (Refer to Black at a to see that extending at will not gain any liberties.)

Black b

Black at b  

After , play reverts to for Black at a.

Black c

Black at c  

a and b are miai for life

forcing first, part 1  

hhw: White can force on the side first...

forcing first, part 2  

hhw: ...and then enclose the Black group.

possible continuation, at  

hhw: seems to allow White to get both groups out by itself.

Tapir tries...

White to play, status of the marked stones?  

Up to all moves were forced. Now there are several variants. (Basic ideas similar to hhw, but omitting his , which gives unnecesarry options to Black.)

There are four crucial points left.

After a White lives if b is sente (threatening to move out and disabling d in the process)

After b White lives with d (a and c miai) or a (undestroyable second eye because of snapback).

After c White can live directly with a (undestroyble second eye because of snapback.)

After d White escape, force Black and then wrap up the whole black group with . As White can make a second eye at a, Black can not win this capturing race.

Continuation Black d  

So, Black playing at a is the only line not yet refuted.

Continuation Black a  

After Black has not many options. Keeping White from getting to the outside is the best play, but White can live easily with a play at c (as Black can't play at d).

Black c fails, White can force at e and than capture with an eye at f

Black f is the only possibly resistance. But ends in disaster.