Revelation tells us that one of the Seven Heads or Kings receives a deadly wound.  Which one not being told, it appears to be the last because the Beast has all of his Heads before one of them is wounded.

             "He is called the Beast that was and is not, even he is the Eighth and is of the Seventh, and goeth into perdition."

                      The only clear answer is that the Seventh Head, the Antichrist, is the one who receives the deadly wound.