In his recent "Immortal Game" against Lazaro Bruzon Batista, Wei Yi initiated his king hunt with the move 22.Rxf7!! from this position
[FEN "3qr1k1/1b1rbp2/p2p2p1/1p1np3/4P3/P2BB2Q/1PP3PP/4RR1K w - - 0 22"]
The annotation to this move said that the next four moves were forced. My question is why the king recapture of the rook 22..., Kxf7 is considered forced, since 22..., Nf6 seems to be a viable alternative, defending against the threatened mate by the queen at h7, saving the knight and trapping the rook?