(;AB[sq]AB[rq]AW[rr]AW[sr]AW[rs]AW[qq]AW[pq]AW[oq]AB[nq]AB[nr]AB[ns]AB[op]AB[pp]AB[qp]AB[qo]C[Black to kill white unconditionally. There are two initial moves, but the playout is much the same.]AB[rn]AP[goproblems] (;B[or];W[rp] (;B[qr];W[sp] (;B[rq];W[sq] (;B[pr]C[White dies!RIGHT]) (;B[ps]C[White is dead!RIGHT]) (;B[qs];W[pr]TR[qr]TR[qs]C[The marked stones are dead and white lives!])) (;B[pr];W[rq]C[Oops! White lives :(]) (;B[ps];W[rq]C[Oops! White lives :(]) (;B[qs];W[pr]TR[qr]TR[qs]C[The marked stones are dead and white lives!])) (;B[pr];W[qr]TR[rq]TR[sq]C[White connects, and the marked stones are dead for two eyes :(])) (;B[qr];W[pr] (;B[ps];W[qs] (;B[or];W[os]C[A ko, but black can kill unconditionally.]) (;B[os];W[rp]TR[rq]TR[sq]C[Oops. White will take the marked stones and live!]) (;B[rp];W[os]C[White lives with ease. Miai at A and B.]LB[or:A]LB[ps:B])) (;B[or];W[ps]C[Oh no! White lives :(])) (;B[pr];W[qr] (;B[ps];W[rp]TR[rq]TR[sq]C[The marked stones are dead and white makes life!]) (;B[os];W[rp]TR[rq]TR[sq]C[The marked stones are dead and white makes life!]) (;B[or];W[rp]TR[rq]TR[sq]C[The marked stones are dead and white makes life!]) (;B[rp];W[or]TR[pr]C[The marked stone is dead and white makes life!])) (;B[ps];W[rp] (;B[qr];W[sp] (;B[rq]C[White is dead! White cannot threaten at A (self-atari). Note that if white captures, black will have to respond to avoid the threat at A.RIGHT]LB[pr:A]) (;B[pr];W[rq]C[Oops! White lives.]) (;B[or];W[rq]C[Oops! White lives :(]) (;B[os];W[rq]C[Oops! White lives.]) (;B[qs];W[rq]C[Oops! White lives.])) (;B[pr];W[qr]C[The marked stones are dead and white makes life!]TR[rq]TR[sq]) (;B[or];W[qr]C[The marked stones are dead and white makes life!]TR[rq]TR[sq]) (;B[ro];W[sp]C[White has miai for life at A and B.]LB[qr:A]LB[rq:B]) (;B[qs];W[qr]TR[rq]TR[sq]C[The marked stones are dead and white lives!])) (;B[rp];W[ps] (;B[pr];W[or]C[The marked stone is dead and white lives!]TR[pr]) (;B[qr];W[pr]C[Sweet life for white.]) (;B[or];W[pr]C[White makes life!])))