martinmadlik #1Rf7+, Kg8, Rd7+ or Rc7+, Kf8 or Kh8, Ng6++but original only solutions is Rf7+, Kg8, Re8+,Qe6,Bxe6+,Kh8,Ng6++ which is longer!
martinmadlik #2Sorry, this is of course wrong. Only original solution is valid! Please, remove this post.
vasfed12 #3yeah, your variation is wrong since it allows for the rook or queen to interpose the bishop check.