Correct answer: Rg2-g1 1.Rg2-g1 ! zugzwang. 1...Kh4-h3 2.Rg1-h1 # 1...g7-g5 2.Rg1-h1 # 1...g7-g6 2.e3-e4 zugzwang. 2...Kh4-h3