(;
AB[ra][sb][rc][qd][rf][od][nd][me][mc][lc][lb][la][nb]
AW[mb][ma][na][oa][nc][oc][pc][qb][rb]
C[Black plays.
Did Go World make a mistake on a life and death problem?

Source:
   Go World #117, Winter 2008-2009, p. 51, problem 8.

Analysis:
    Myron Souris]
(;
B[ob]
C[Go World gives this play as the only killing move.];
W[pb];B[qa]
C[And yes, White is dead.  However, ...]
)
    (;
    B[qa]
    C[Go World says this move is a mistake!?  But this play also seems to kill White.]
    (;
    W[ob]
    C[Go World gives this defense.]
    (;
    B[pa]
    C[Go World only gives this line, which seems to let White live.];
    W[pb]
    C[And White makes a 2nd eye after capuring 3 stones.]
    )
        (;
        B[qc]
        C[But Black has this atari to destroy White's 2nd eye!  White dies.]
        )
    )
        (;
        W[qc]
        C[Note that White could try this counter-attack.];
        B[ob]
        (;
        W[rd];B[re];W[sc];B[pa];W[pd];B[pe];W[qe]
        C[White captures a couple stones on the right edge, but ...];
        B[qf]
        C[... White has only 1 eye, and cannot escape to the center.]
        )
            (;
            W[pb]
            C[White doesn't have time to capture here.];
            B[re]
            C[White has only 1 eye.]
            )
        )
    )
)

