(;
AB[pd][of][pf]
AW[pc][qf][pg]
C[Black's response to the marked play?

Source:
    Go World #21, pp. 39-40
    "Some Popular Trick Moves", Kato Masao 9p]
TR[pc]
(;
B[oc]
C[Black often blocks here, but this move falls for the trick.];
W[qc]
(;
B[ob];W[re]
C[Letting White link up is unsatisfactory.]
)
    (;
    B[qd]
    C[Blocking here may seem OK, but ...];
    W[ob]
    C[... after White's hane, the result is very bad for Black.]
    )
)
    (;
    B[qe]
    C[Block here is correct.]
    (;
    W[oc]
    (;
    B[qg]
    C[But this continuation is bad.];
    W[lc]
    TR[pc]
    C[White's shape is good, so the marked invasion has succeeded.]
    )
        (;
        B[mc]
        C[Instead, Black must block here.]
        (;
        W[rc]
        C[If White takes the corner, ...];
        B[qg]
        C[... now this cut and the marked exchange satisfy Black.]
        TR[mc][rc]
        )
            (;
            W[qg]
            C[Connecting looks unreasonable.];
            B[qc];W[qb];B[rc]
            C[White does not have 2 eyes.]
            )
        )
    )
        (;
        W[qc]
        C[If White descends, ...];
        B[nc]
        C[... Black's placement is the strongest counter.]
        )
    )
)

