(;GM[1]FF[4]SZ[9]
GN[Bill's idea]
PC[http://senseis.xmp.net/?MutualDamage]AP[GoWiki:2009]
DT[2009-04-22]
C[Diagram from http://senseis.xmp.net/?MutualDamage

Bill's idea]
PL[B]

AB[db][dc][dd][de][cf][ef][eg][eh]
AW[eb][ec][ed][ee][ge][ff][fg][fh]

;B[ea]C[B1]MN[1]
;W[fa]C[W2]MN[2]
;B[da]C[B3]MN[3]
;W[ei]C[W4]MN[4]

;
)
