Correct answer: Nd51...e:d4 2.Q:f4# 1...f3 2.Q:f3# 1.R:e6?? (2.Q:f4#) but 1...d:e6! 1.Rh2?? (2.Re2#) but 1...f3! 1.Bg2+?? 1...f3 2.Q:f3# but 1...Ke3! 1.d: