(;
AB[nm][rn][no][np][nq][nr][ns][po][qo][rp][sp][os]
AW[op][oq][or][pp][qp][pr][ps][rr][ss]
C[Black plays.]
(;
B[qq]
C[This placement definitely attacks White's eye shape, but ...];
W[rq]
C[... White seems to have multiple ways to create a 2nd eye in the corner.];
B[qr]
C[A very easy move to overlook, especially in a game!]
(;
W[qs];B[sq]
C[White's liberty shortage prevents making the 2nd eye.]
)
    (;
    W[sq];B[qs]
    C[And White dies from not being able to approach from either side.]
    )
)
    (;
    B[rs]
    C[Fails.];
    W[sr]
    C[White lives.]
    )
    (;
    B[sr]
    C[This throw-in also fails.];
    W[rs];B[qq]
    C[Too late.];
    W[rq];B[qr];W[sq]
    )
)

