(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]
RU[Japanese]SZ[19]KM[0.00]
PB[Black to play and kill]AW[oq][pq][qq][sq][or][rr][os][ps]AB[mp][op][pp][qp][rp][nq][rq][nr][pr][ns][rs]
(;B[sp]C[Black should start here.]
(;W[sr]C[If White connects....]
;B[qr]C[.... Black sacrifices another stone...]
;W[qs]
;B[qr]C[... which sets up White for the double snap-back shape.])
(;W[qr]C[White cannot take as he clearly dies.]
;B[sr])
(;W[qs]C[This is self-atari.]
;B[qr])
(;W[ss]C[This looks like a ko shape...]
;B[sr]C[... but Black takes two stones.]))
(;B[qr]C[If Black plays this move first, thinking it is a tesuji...]
;W[qs]
;B[sp]C[... then after this move White will not connect as expected.]
;W[ss]C[White will capture instead, setting up a ko.]
;B[sr])
(;B[sr]
;W[ss]C[This is a ko too.])
(;B[qs]C[This lets White to live.]
;W[qr]
;B[sr]
;W[ss]))
