(;GM[1]FF[4]CA[UTF-8]AP[CGoban:2]ST[2] RU[NZ]SZ[19]KM[0.00] PW[White]PB[Black]AW[oa][nb][pb][rb][mc][nc][qc][rc][sc][ld][md][rd][li][mi][nj][oj][pj][mk][qk][rk][sk]AB[ob][oc][pc][nd][pd][qd][sd][le][me][ne][re][lh][mh][nh][qh][ni][oi][pi][qj][rj][sj]TR[sc]C[How should black respond to the marked stone?] (;B[se]CR[se] ;W[qe]CR[qe] (;B[rf]CR[rf] ;W[rg]CR[rg] (;B[qf]CR[qf] ;W[pe]CR[pe] ;B[od]CR[od] ;W[pf]CR[pf] (;B[qg]CR[qg]C[RIGHT White's going nowhere.]) (;B[pg]CR[pg] ;W[qg]CR[qg])) (;B[pe]CR[pe] ;W[qf]CR[qf]) (;B[qg]CR[qg] ;W[qf]CR[qf]) (;B[sg]CR[sg] ;W[qf]CR[qf])) (;B[qf]CR[qf] ;W[pe]CR[pe] ;B[od]CR[od] ;W[rf]CR[rf]) (;B[pe]CR[pe] ;W[qf]CR[qf] ;B[rf]CR[rf] ;W[rg]CR[rg])) (;B[rf]CR[rf] ;W[se]CR[se] ;B[sf]CR[sf]C[Black can do better]) (;B[qe]CR[qe] ;W[se]CR[se] ;B[sf]CR[sf] ;W[sd]CR[sd] ;B[rf]CR[rf]C[Black can do better.]) (;B[sf]CR[sf] ;W[se]CR[se]C[Black can do better than ko.]))