(;AB[qb]AB[qc]AB[qa]AB[rb]AB[pb]AW[ob]AW[oc]AW[pc]AW[nd]AB[pd]AB[pe]AB[pf]AW[qd]AW[rd]AW[rc]AB[re]C[Black to start a ko in the best way possible.]AW[sb]AP[goproblems] (;B[qe];W[ra];B[sa]C[Direct ko, black captures first and no local threats for white.RIGHT]) (;B[sd];W[ra];B[sa]C[Direct ko, black captures first and no local threats for white.RIGHT]) (;B[sc];W[sd] (;B[qe];W[ra];B[sa]C[Direct ko and black captures first.RIGHT]) (;B[se];W[ra];B[sa]C[Direct ko and black captures first.RIGHT]) (;B[sa];W[ra];B[sa]C[Two stage ko in white's favour.])) (;B[sa];W[ra]C[Direct ko, but white captures first and she has a local threat at A.]LB[sc:A]) (;B[ra];W[oa] (;B[qe];W[pa]C[No ko at all.]) (;B[sd];W[pa]C[No ko at all.]) (;B[sc];W[pa];B[sa];W[sb]C[No ko at all.])) (;B[pa];W[oa]C[No ko at all.]) (;B[oa];W[na] (;B[pa];W[ra]) (;B[ra];W[pa]C[Two step ko in white's favour.]) (;B[sa];W[ra]C[Direct ko, but white captures first and she has a local threat at A.]LB[sc:A]) (;B[qe];W[pa]C[Direct ko, but white captures first and she has a local threat at A.]LB[sc:A]) (;B[sd];W[pa]C[Direct ko, but white captures first and she has a local threat at A.]LB[sc:A]) (;B[sc];W[sd] (;B[qe];W[pa]C[Direct ko, but white captures first.]) (;B[se];W[pa]C[Direct ko, but white captures first.]))))