Correct answer: Nc31...Nb4/Nc1/Nc3 2.R:b4# 1.f4?? (2.Qf2#/Qg1#) 1...d1Q/d1R 2.Qf2# but 1...d1N! 1.Rc2?? (2.Rc4#) but 1...Nc3! 1.N