I enjoyed it. Thanks, Decoy. I figured there was a forced mate but I can't claim I saw it clearly from the beginning. It was pretty intuitive as I assumed I had to keep black in check or white would experience a similar problem starting with ...Rf2+. In that sense the puzzle could also be titled, "what a difference a tempo makes!"
edit: I realize now that white has f2 guarded so there's no forced mate on white that I can see. Good thing I didn't see that earlier. Thinking that white was probably one tempo away from suffering a forced mate as well helped me solve the puzzle :). Well done.
From one of my games, Good luck!