Correct answer: Nc41...c5 2.Nb5# 1.Nc8?? zz 1...Kc4 2.Qb4# but 1...c5! 1.Nd7?? zz 1...Kc4 2.Qe4#/Qh4#/Qc5#/Qb4# but 1...c5! 1.N:a4?? zz 1..