The Beast’s fatal wound is its sixth head. (Rev 13:3-4)

The Beast has 7 heads, symbolizing the 7 phases of the Beast. It has a fatal wound on one of its heads. Revelation 17 describes the same fatal wound and identifies it is the sixth head. After the fatal wound has been healed, the entire world will follow after the Beast (Rev 13:4). This will be the seventh and final phase of the Beast.