Correct answer: O-O1...Bg4/Be8/Bc6/Bb5/Ba4/e6 2.R:g4# 1.O-O! (2.Rf3#/Re3#) 1...g4 2.Re3# 1...Bg4 2.R:g4# 1...Bc6 2.Rf3#/Rg4#
