Correct answer: Kf11...K:c1 2.O-O# 1...Q:b2 2.Q:b2# 1...R:g5/Rg7/Rg8/R:f6/Rh6 2.Q:c2# 1.B:g6?? (2.Q:c2#) 1...Q:b2 2.Q:b2# but 1...f:g6! 1.