CheckMate!
Why move the white rook? Why not Knight g8 mate and end it? Oops, I forgot the black bishop guards that square. That explains my rating, I often overlook these little details. 
Why move the white rook? Why not Knight g8 mate and end it?
Look at Black's Bishop. If the White Knight checks on g8, Black's Bishop would simply capture it.
Er, I guess except it doesn't work if black doesn't take the rook.
You're right, the "solution" in no way forces the Bishop to move, and without it moving White has no mate, at least not a forced one on the next move. Bad puzzle.
Er, I guess except it doesn't work if black doesn't take the rook.
You're right, the "solution" in no way forces the Bishop to move, and without it moving White has no mate, at least not a forced one on the next move. Bad puzzle.
I agree, for instance 1. Rg4 Nf5+ and the mate obviously doesn't work.