[FEN "6k1/R7/7p/3PB2N/2b1p1P1/4P1K1/r4PP1/8 w -"]

42. Nf6+ Kf8 43. Bd6#


w b wb bw | w b wb bw

w     an



42. Nf6+      an



42...Kf8      an



43. Bd6#      an