(;GM[1]FF[4]CA[UTF-8]AP[CGoban:2]ST[2] RU[Japanese]SZ[19]KM[0.00] PW[Weiß]PB[Schwarz]AW[ln][mn][nn][qn][lo][qo][kp][rp][kq][rq][kr][rr][ks][qs][rs]AB[mo][no][oo][po][lp][qp][lq][oq][qq][lr][qr][ls][ps]C[White to play - what can he do?]PL[W] (;W[pr]CR[pr] (;B[os]CR[os]C[Black offers the strongest resistance!] (;W[or]CR[or] ;B[ns]CR[ns] (;W[nr]CR[nr] ;B[ms]CR[ms] (;W[mp]CR[mp] ;B[mq]CR[mq] (;W[nq]CR[nq] ;B[np]CR[np] ;W[pp]CR[pp]C[RIGHT]) (;W[pp]CR[pp] ;B[pq]CR[pq] ;W[nq]CR[nq]C[RIGHT])) (;W[pq]CR[pq] ;B[pp]CR[pp] ;W[nq]CR[nq] ;B[np]CR[np]C[This is only a ko, White can do better.]) (;W[pp]CR[pp] ;B[pq]CR[pq] (;W[nq]CR[nq] ;B[op]CR[op] ;W[mp]CR[mp] ;B[np]CR[np]C[Black saves all his stones & all his points...]) (;W[mp]CR[mp] ;B[nq]CR[nq]C[White played n4 one move to late.])) (;W[nq]CR[nq] ;B[pq]CR[pq] (;W[mp]CR[mp] ;B[np]CR[np]C[This doesn't work.]) (;W[op]CR[op] ;B[pp]CR[pp] (;W[np]CR[np] ;B[mp]CR[mp] ;W[pn]CR[pn] ;B[mq]CR[mq]C[White is one move to late]) (;W[mp]CR[mp] ;B[np]CR[np]C[Black saved his stones & his points....])))) (;W[pq]CR[pq] ;B[pp]CR[pp] ;W[nr]CR[nr] ;B[ms]CR[ms] ;W[nq]CR[nq] ;B[np]CR[np]C[This is only a ko, White can do better.]) (;W[pp]CR[pp] ;B[pq]CR[pq] ;W[nr]CR[nr] ;B[ms]CR[ms] ;W[nq]CR[nq] ;B[op]CR[op] ;W[mp]CR[mp] ;B[np]CR[np]C[This doesn't work.])) (;W[mp]CR[mp] ;B[nr]CR[nr])) (;B[pq]CR[pq] ;W[os]CR[os] ;B[or]CR[or]C[This is of course better for Black than the main variation, but....])) (;W[mp]CR[mp] ;B[nr]CR[nr]))