Correct answer: g51.Bf5[A]? zz 1...Ng2[a]/Ng6/[б]//Nf3[a]/B:f4 2.g5#[Б] 1...Bg5[c] 2.Q:e3#[C] 1...Bg7/Bf8 2.Q:e3#[C]/g5#[Б] but 1...N:f5! 1.g5[Б]
