Correct answer: Rg8-g5 1.Rg8-g5 ! zugzwang. 1...g4-g3 2.h2*g3 # 1...f5-f4 2.Rg5*g4 danger: 3.Rg4-g1 # 1...e6-e5 2.Rg5*f5 zugzwang.
