(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]
RU[Japanese]SZ[19]KM[0.00]
PB[Black to play]AW[fq][gq][jq][kq][lq][dr][er][gr][ir][lr][fs][hs][is]AB[eo][ho][dp][gp][jp][kp][lp][pp][dq][hq][iq][mq][nq][cr][hr][jr][pr]C[Black to play and capture the four L-stones]
;B[ks]C[This is the right first play, but it is Black's next play that is harder to see.]
(;W[ls]C[If White descends the stones quickly run out of liberties.]
;B[mr]C[White will self-atari if atari on the black ones.])
(;W[kr]C[This is where Black needs a good play....]
(;B[mr]C[... as this play fails.]
;W[js]
;B[ms]
;W[ls])
(;B[ls]C[So Black has to play here and chase White out.]
;W[mr]
;B[ms]
;W[nr]
;B[ns]
;W[or]
;B[os]
;W[oq]
;B[op]
;W[js]
;B[ps]
;W[ds]C[White has play here to ensure two eyes.]
;B[pq]C[White is short of liberties.]))
(;W[mr]C[White can try this.]
(;B[nr]C[Balck here clearly fails.]
;W[kr]
;B[ms]
;W[js])
(;B[ls]C[Again Black has to play along the edge.]
;W[nr]
;B[ms]
;W[or]
;B[ns]
;W[oq]
;B[op]
;W[pq]
;B[qq]
;W[qr]
;B[ps]C[White is short of liberties but Black is not.])))
