Problem 20778 goproblems.com


Author	Xenor	Created	2016-02-14
Difficulty	8 dan (history)	Source	Game on KGS (slightly modified).
AVG solve time	108 sec	Stars	5 (3 votes)
User attempts	30 / 305	Collections	Semeai / Capturing Race, Corner based, Lack of Liberties (Damezumari), Tesuji
Genre	life and death ⓢ	Your attempts	N/A
Similar problems
Created	2016-02-14
Source	Game on KGS (slightly modified).
Stars	5 (3 votes)
Collections	Semeai / Capturing Race, Corner based, Lack of Liberties (Damezumari), Tesuji
Your attempts	N/A

(;AW[qs]AW[qr]AW[qq]AW[rq]AW[sr]AB[ps]AB[pr]AB[pq]AB[oq]AB[nq]AB[mq]AB[lq]AB[kq]AB[mr]AW[jq]AW[kr]AW[lr]AW[ir]AB[ls]AW[js]AW[kp]AW[lp]AW[mp]AW[np]AW[op]AW[pp]AW[os]AB[qp]AB[rp]AB[qo]AB[po]AB[on]AB[om]AW[oo]AW[pn]AW[jp]AB[nr]AB[rs]AW[qn]TR[po]TR[qo]TR[qp]TR[rp]C[Our mighty hero Blackura is about to get caught by the evil White. The situation seems desperate.'There are plenty of ko threats on the goban. If at least I could trigger a ko...']AP[goproblems] (;B[so] (;W[rn]C[];B[sq];W[sp]C[The ko you were looking for.RIGHT]) (;W[sn]C[Trick move detected.Blackura to punish !CHOICE] (;B[rn] (;W[sq]C[CHOICE] (;B[rr];W[ns] (;B[sm];W[ks];B[sp];W[ms];B[ss]C[Blackura didn't get tricked. Mission accomplished !!RIGHT]) (;B[sp];W[ro]C[Ooops !!]) (;B[ro];W[ks];B[sm];W[ms];B[sp];W[or]C[A huge group was lost in the battle.]) (;B[rm];W[ks] (;B[sm];W[ms];B[sp];W[or]) (;B[sp];W[ro]C[Ooops !!]) (;B[qm];W[jm]C[White plays tenuki, the black group is still dead.]) (;B[pm];W[jm]C[White plays tenuki, the black group is still dead.])) (;B[qm];W[ks] (;B[sp];W[ro]C[Ooops !!]) (;B[pm];W[ms];B[sp];W[or]C[A huge group was lost in the battle.])) (;B[pm];W[ks] (;B[sp];W[ro]C[Ooops !!]) (;B[qm];W[ms];B[sp];W[or]C[A huge group was lost in the battle.]))) (;B[rm];W[ns] (;B[sm];W[ks] (;B[rr];W[ms];B[sp];W[or]C[A huge group was lost in the battle.]) (;B[ss];W[ms];B[sp];W[or]) (;B[sp];W[ms] (;B[rr];W[or]) (;B[ss];W[or]C[A huge group was lost in the battle.]))) (;B[rr];W[ks] (;B[sm];W[ms];B[sp];W[or]) (;B[sp];W[ro]C[Ooops !!]) (;B[qm];W[jm]C[White plays tenuki, the black group is still dead.]) (;B[pm];W[jm]C[White plays tenuki, the black group is still dead.])) (;B[sp];W[ro]C[Ooops !!]) (;B[qm];W[jm]TR[kq]TR[lq]TR[mq]TR[nq]TR[oq]TR[pq]TR[pr]TR[ps]TR[nr]TR[mr]TR[ls]C[White plays tenuki, the black group is still dead.]) (;B[ss];W[ks] (;B[sm];W[ms];B[sp];W[or]C[A huge group was lost in the battle.]) (;B[sp];W[ro]C[Ooops !!])) (;B[pm];W[jm]C[White plays tenuki, the black group is still dead.]) (;B[ro];W[ks] (;B[rr];W[ms];B[sp];W[or]C[A huge group was lost in the battle.]) (;B[ss];W[ms];B[sp];W[or]C[A huge group was lost in the battle.]) (;B[sp];W[ms] (;B[rr];W[or]) (;B[ss];W[or])))) (;B[sm];W[sp];B[ro];W[rm]C[Ooops !!]) (;B[sp];W[ro]C[Ooops !!]) (;B[ss];W[ns] (;B[sm];W[ks];B[sp];W[ms];B[rr]C[RIGHT]) (;B[sp];W[ro]C[Ooops !!]) (;B[ro];W[ks];B[sm];W[ms];B[sp];W[or]C[A huge group was lost in the battle.]) (;B[rm];W[ks] (;B[sm];W[ms];B[sp];W[or]C[A huge group was lost in the battle.]) (;B[sp];W[ro]C[Ooops !!])) (;B[qm];W[ks] (;B[sp];W[ro]C[Ooops !!]) (;B[pm];W[ms];B[sp];W[or]C[A huge group was lost in the battle.])) (;B[pm];W[ks] (;B[sp];W[ro]C[Ooops !!]) (;B[qm];W[ms];B[sp];W[or]C[A huge group was lost in the battle.]))) (;B[ro];W[rm];B[sm];W[sp]) (;B[ns];W[sp]C[Nice try, but this won't end as a ko !]) (;B[qm];W[ns] (;B[sp];W[ro]C[Ooops !!]) (;B[pm];W[ks];B[sp];W[ms] (;B[rr];W[or]C[A huge group was lost in the battle.]) (;B[ss];W[or]C[A huge group was lost in the battle.])) (;B[rr];W[ks] (;B[sp];W[ro]C[Ooops !!]) (;B[pm];W[ms];B[sp];W[or]C[A huge group was lost in the battle.])) (;B[ss];W[ks] (;B[sp];W[ro]C[Ooops !!]) (;B[pm];W[ms];B[sp];W[or]C[A huge group was lost in the battle.]))) (;B[pm];W[ns];B[qm];W[ks] (;B[sp];W[ms] (;B[rr];W[or]C[A huge group was lost in the battle.]) (;B[ss];W[or]C[A huge group was lost in the battle.])) (;B[rr];W[ms];B[sp];W[or]C[A huge group was lost in the battle.]) (;B[ss];W[ms];B[sp];W[or]C[A huge group was lost in the battle.]))) (;W[sp]C[Ko, but black would take first. Worse than the main variation.];B[sq])) (;B[sq];W[sp]C[Ok, you got your ko. But T6 is a trick move, you should punish without ko !])) (;W[sq]C[What if white refuses the ko ?CHOICE] (;B[rr];W[sn]C[Only move.] (;B[rn];W[ns] (;B[sm];W[ks];B[sp];W[ms];B[ss]C[Blackura didn't get tricked. Mission accomplished !!RIGHT]) (;B[sp];W[ro]C[Ooops !!]) (;B[ro];W[ks];B[sm];W[ms];B[sp];W[or]C[A huge group was lost in the battle.]) (;B[rm]) (;B[qm];W[ks] (;B[sp];W[ro]C[Ooops !!]) (;B[pm];W[ms];B[sp];W[or]C[A huge group was lost in the battle.])) (;B[pm];W[ks] (;B[sp];W[ro]C[Ooops !!]) (;B[qm]))) (;B[ns];W[rn]C[Nice try, but this won't end as a ko !]) (;B[sp];W[ro]C[Ooops !!]) (;B[rm];W[rn]C[Ooops !!]) (;B[qm];W[rn]C[Ooops !!])) (;B[ss];W[sn]C[Only move.] (;B[rn];W[ns] (;B[sm];W[ks];B[sp];W[ms];B[rr]C[RIGHT]) (;B[sp];W[ro]C[Ooops !!]) (;B[ro];W[ks];B[sm];W[ms];B[sp];W[or]C[A huge group was lost in the battle.]) (;B[rm]) (;B[qm];W[ks] (;B[sp];W[ro]C[Ooops !!]) (;B[pm];W[ms];B[sp];W[or]C[A huge group was lost in the battle.])) (;B[pm];W[ks] (;B[sp];W[ro]C[Ooops !!]) (;B[qm]))) (;B[sp];W[ro]C[Ooops !!]) (;B[ns];W[rn]C[Nice try, but this won't end as a ko !]) (;B[qm];W[rn]C[Ooops !!]) (;B[rm];W[rn]C[Ooops !!])) (;B[rn];W[sp];B[ro];W[rm]C[Ooops !!]) (;B[sp];W[sn]C[Ooops !!]) (;B[ro];W[rn]C[Ooops !!]) (;B[sn];W[sp];B[ro];W[sm]C[Ooops !!]) (;B[rm];W[sp];B[ro];W[rn]C[Ooops !!]) (;B[sm];W[sp];B[ro];W[sn];B[rn];W[rm]C[Ooops !!]))) (;B[sq];W[sp];B[ro];W[rn]C[Ooops !!]) (;B[ro];W[rn];B[sq];W[sp]) (;B[sp];W[so] (;B[ro];W[rn];B[sn];W[sq]C[Ooops !!]) (;B[sq];W[ro]C[Ooops !!]) (;B[sn];W[rn];B[ro];W[sq]C[Ooops !!]) (;B[rn];W[sq] (;B[ro];W[rm];B[sn];W[sm]C[Ooops !!]) (;B[qm];W[ro]C[Ooops !!]) (;B[pm];W[qm]C[Ooops !!]))) (;B[rn];W[sp];B[ro];W[rm] (;B[so];W[sn]C[Ooops !!]) (;B[qm] (;W[sn]C[Not better than the other variation.];B[pm];W[so];B[rl]) (;W[ns]C[CHOICE] (;B[so];W[sn]C[Ooops !!]) (;B[pm];W[ks];B[so];W[ms];B[sq];W[or]C[A huge group was lost in the battle.]))) (;B[sn];W[sm]C[Ooops !!]) (;B[pm];W[qm]C[Ooops !!])) (;B[sn];W[sp];B[ro];W[rn]C[Ooops !!]) (;B[rr];W[ss] (;B[sp];W[so] (;B[rr];W[ro]C[Ooops !!]) (;B[ro];W[rn];B[sn];W[sq]C[Ooops !!]) (;B[rn];W[sq];B[ro];W[rm];B[sn];W[sm]C[Ooops !!]) (;B[rs];W[ro]C[Ooops !!])) (;B[ro];W[rn];B[sq];W[sp]C[Ooops !!]) (;B[so];W[rn] (;B[sq];W[ro]C[Ooops !!]) (;B[sp];W[sn]C[Ooops !!])) (;B[rn];W[sp];B[ro];W[rm] (;B[so];W[sn]C[Ooops !!]) (;B[qm] (;W[sn]C[Not better than the other variation.];B[pm];W[so];B[rl]) (;W[ns]C[CHOICE] (;B[so];W[sn]C[Ooops !!]) (;B[pm];W[ks];B[so];W[ms]LB[rr:a]C[Beginning with a made the things worse !!])))) (;B[sn];W[sp];B[ro];W[rn]C[Ooops !!])) (;B[ss];W[sp]C[Ooops !!]) (;B[ns];W[sp]C[Nice try, but this won^t end as a ko !]))