Correct answer: Nb51...Ng4/Ng8/Nf5/Nf7 2.Qf7# 1...f5 2.Qe5# 1...R:b3/Rb5/Rb6/R:b7/c4 2.Qe4# 1...Rc4 2.b:c4# 1...Re4 2.f:e4#/Q:e4# 1.N