(;CA[gb2312]AB[bp][cp][dp][ep][fq][fr][er][hr][ir]AW[ar][br][cq][dq][eq][dr][cs][fp][gp][hq][iq][jq][lq]C[Black to play and live]AP[MultiGo:4.4.4]SZ[19]AB[bq]MULTIGOGM[1]
(;B[jr]C[Expanding the eye space is normal, but it doesn't work here];W[kr]
(;B[es]C[Black has a weakness so this fails];W[gr];B[gq];W[gs];B[hs];W[js];B[fs]
;W[ds]C[Black only has one eye])
(;B[js]C[Again Black has a weakness];W[es];B[fs];W[ds]
(;B[hs]
;W[gr]C[Black is short of liberties to capture this stone])
(;B[gq]
;W[hs]C[Snap-back shape])))
(;B[bs]C[This is the correct play]
(;W[gr];B[gq];W[gs];B[hs];W[jr];B[ds];W[es]
;B[fs]C[A ko is the solution, the best result for Black here.])
(;W[as]C[If white captures, Black easily lives];B[es];W[gr]
;B[ds]C[White's corner is dead])))
