Correct answer: Rf61...Nf3/Ng4/Ng6/Nd3/Nd7/Nc4/Nc6 2.Nd7# 1...N:f7 2.Nd7#/Re8# 1.Rc7?? (2.Re8#) 1...N:f7 2.Nd7# but 1...Nd7!
