Correct answer: Na41...f6/f5 2.Bc4# 1.Nc6?? (2.Na7#) but 1...K:c6! 1.Nb7?? (2.Qa4#) but 1...Kc6! 1.Ke2?? zz 1...f6/f5 2.Bc4# but 1...e3! 1.K:e4?? zz
