(;
AB[on][qo][qp][qq][ro][so][np][nq][nr][op][lr]
AW[rp][rq][oq][or][os][pq][qr]
C[Black plays.];
B[rr]
C[A classic corner attacking tesuji.];
W[sr];B[rs]
(;
W[sq]
C[A classic defensive tesuji.]
(;
B[sp]
C[Black falls for the trap.];
W[qs];B[ss];W[rq]
C[White makes a 2nd eye in the corner.]
)
    (;
    B[qs]
    C[Correct.];
    W[ps]
    C[A ko is the best result for both sides.]
    )
)
    (;
    W[qs]
    C[A mistake.];
    B[sq];W[ss];B[rr];W[rs];B[sp]
    C[Ouch.  White dies.]
    )
)

