(;AB[ns]AB[nr]AB[nq]AB[np]AB[pn]AW[om]AW[no]AW[mo]AW[mp]AW[mq]AW[mr]AW[ms]AB[op]AW[qm]AW[pm]AB[qn]AB[sn]AB[rn]AW[oo]AB[po]AW[on]AW[pp]AW[qp]AB[pq]AB[rm]AW[ql]AB[rl]AW[rk]AW[sl]AW[qk]AB[qq]AW[sk]C[Remember, Black wins any ko. Avoid ko at all cost.]AB[or]AP[goproblems] (;W[ro];B[rp]) (;W[rq];B[rp]) (;W[rp] (;B[rq] (;W[sm];B[sp]) (;W[so];B[ro] (;W[sm];B[sp]) (;W[sp];B[sq]) (;W[qo];B[sp]) (;W[sq];B[sr])) (;W[sp];B[sq]C[Seki! Best for both, but Black has taken it easy here.CHOICERIGHT]) (;W[sq];B[sp]C[Black sets up a possible ko] (;W[ro];B[sr]) (;W[so];B[sr] (;W[sm];B[sp]C[Ko, and black captures due to more ko threats]) (;W[ro];B[sp]C[Ko, and black captures due to more ko threats]) (;W[sp];B[ro]) (;W[qo];B[sp]C[Ko, and black captures due to more ko threats])) (;W[rr];B[sr]) (;W[sm];B[sr]) (;W[sr];B[so])) (;W[ro];B[sp];W[sm];B[so]) (;W[qo];B[sp])) (;B[sp]C[Rauli suggested this move. Black is prepared to incur a loss just to make unconditional life hard on White.] (;W[rq];B[rr] (;W[sr];B[rs] (;W[qr];B[pr] (;W[ro];B[so] (;W[sm];B[qs];W[sq]C[Correct! Black now loses the upper part as punishment for underestimating your strength.CHOICERIGHT]) (;W[sq]C[Correct! Black now loses the upper part as punishment for underestimating your strength.RIGHT]) (;W[qs];B[ps]) (;W[ps];B[sq])) (;W[sm];B[ro];W[sq]C[Ko]) (;W[sq];B[ro]C[Ko]) (;W[qo];B[ro]) (;W[so];B[ro] (;W[sq]C[Ko]) (;W[sm];B[qs];W[sq]C[Ko]))) (;W[ro];B[so] (;W[sq];B[ss]) (;W[qr];B[sq]) (;W[sm];B[ss])) (;W[sq];B[ro] (;W[so]C[Ko]) (;W[qr];B[qo]C[Ko]) (;W[sm];B[ss]C[Ko])) (;W[so];B[ro] (;W[sq]C[Ko]) (;W[sm];B[ss]))) (;W[sq];B[sr] (;W[so];B[ro]C[Ko]) (;W[ro];B[so]) (;W[qo];B[ro]) (;W[sm];B[ro]C[Ko])) (;W[qr];B[pr] (;W[sr];B[qs] (;W[sq];B[ro] (;W[so];B[rs] (;W[sm];B[sp]C[Ko]) (;W[sp];B[ss]) (;W[qo];B[sp]C[Ko]) (;W[ss];B[sp]C[Ko])) (;W[rs];B[ss] (;W[so];B[rs];W[sm];B[sp]C[Ko]) (;W[sm];B[qo])) (;W[ss];B[rs]C[Ko]) (;W[qo];B[ss]) (;W[sm];B[rs]C[Ko])) (;W[rs];B[ss] (;W[sq];B[rs] (;W[so];B[ro];W[sm];B[sp]C[Ko]) (;W[ro];B[so]) (;W[qo];B[ro]) (;W[sm];B[ro]C[Ko])) (;W[ro];B[sq]) (;W[so];B[ro] (;W[rs]C[Ko]) (;W[sm];B[sq])) (;W[qo];B[sq])) (;W[ss];B[ro] (;W[sq];B[rs]C[Ko]) (;W[sm];B[rs])) (;W[ro];B[so] (;W[sq];B[ss]C[Ko]) (;W[rs];B[ss]C[Ko]) (;W[ss];B[rs]) (;W[sm];B[ss]C[Ko])) (;W[so];B[ro] (;W[sq];B[rs]C[Ko]) (;W[rs];B[ss]C[Ko]) (;W[ss];B[rs]) (;W[sm];B[rs];W[sq]C[Ko])) (;W[sm];B[ro] (;W[sq];B[rs]C[Ko]) (;W[ss];B[rs]) (;W[rs];B[ss]C[Ko]))) (;W[qs];B[sq]) (;W[sq];B[sr] (;W[so];B[ro];W[sm];B[sp]C[Ko]) (;W[ro];B[so]) (;W[qo];B[ro]) (;W[sm];B[ro]C[Ko])) (;W[ro];B[sq]) (;W[so];B[sr] (;W[sq];B[ro];W[sm];B[sp]C[Ko]) (;W[ro];B[sq]) (;W[sm];B[ro]) (;W[qo];B[ro])) (;W[rs];B[sr] (;W[sq];B[qs] (;W[so];B[ro]C[Ko]) (;W[ro];B[so]) (;W[qo];B[ro]) (;W[sm];B[ro]C[Ko])) (;W[ro];B[sq]) (;W[so];B[ro]) (;W[sm];B[sq]))) (;W[ro];B[sq]) (;W[so];B[ro] (;W[sq];B[sr]C[Ko]) (;W[sr];B[qo]) (;W[sm];B[sq])) (;W[sm];B[sq])) (;W[sq];B[rq] (;W[so];B[sr] (;W[sm];B[sp]C[Ko, and black captures due to more ko threats]) (;W[ro];B[sp]C[Ko, and black captures due to more ko threats]) (;W[sp];B[ro]) (;W[qo];B[sp]C[Ko, and black captures due to more ko threats])) (;W[ro];B[sr]) (;W[sm];B[sr]) (;W[rr];B[sr]) (;W[sr];B[so])) (;W[rr];B[rq]) (;W[ro];B[rq];W[sm];B[so]) (;W[so];B[ro] (;W[rq];B[rr] (;W[sq];B[sr]C[Ko]) (;W[sr];B[qo]) (;W[sm];B[sq])) (;W[sq];B[rq] (;W[so];B[sr]) (;W[sm];B[qo])) (;W[sm];B[rq])) (;W[sm];B[rq]))) (;W[sm];B[rp]) (;W[qo];B[rp]) (;W[so];B[rp]) (;W[sp];B[rp]))