Just so everyone understands, when we read Revelation 13, we see both the entire empire system, and we see the individual at the head of the system. How can we tell the difference? When it says, "one of its heads", how do we interpret that?
When describing the beast of Rev. 13:1-2, John writes that the beast has ten crowns upon its ten horns. Now this certainly indicates something specific about the ten kings of Rev. 17:12. In Rev. 17:10, John tells us that the "sixth" is. In Rev. 17:12, he tells us that the ten kings have received no kingdom "as yet". This "as yet" clues us into the fact that during the reign of the "sixth" who "is" the ten kings have not yet risen to power with their kingdom. Therefore, by deduction, we can surmise that it is only during the reign of either the "seventh" or "eighth" that the ten kings can give the "scarlet-colored beast" of Rev. 17 their kingdom (Rev. 17:12).
I highlighted "scarlet-colored beast" because it is to him--the eighth king--the ten kings will receive power as kings for one hour. According to Rev. 17:8, this hour cannot begin until the scarlet-colored beast ascends from the bottomless pit. In other words, there is much more than mere co-existence of the ten kings and the antichrist required for the "one hour" to begin. In Rev. 17:17, they must give the scarlet-colored beast their kingdom. And it is God himself that will perform it.
This all relates back to Orange's question about how we are to read the "one of its heads" that is wounded. The fact that he only has seven heads, and when the sixth head who "is" was reigning at a time when the ten horns "have received no kingdom as yet" clues us into the idea that the only head the ten kings can reign together with is the seventh.
a) All ten horns exist on one head
b) The head that all ten horns exist on can only represent the seventh
The most popular theory is that the seventh head is wounded being the antichrist before his head wound. Then the antichrist becomes the eighth at that point in time.
The healing of the deadly wound inflicted upon the ten-horned head causes the beast of Rev. 13:1-2 to become "the great red dragon of Rev. 17.
All of this is a replay of Esau selling his birthright to Jacob in Gen. 25. After Esau sold his birthright, his name became "Edom" (red), and he despised his birthright. Same thing happened with Judas in John 12. Jesus feeds Judas the bread, Judas hurries off and it suddenly becomes night. Satan enters him and Judas sells out Jesus for 30 pieces of silver. Both despised their birthright. Joshua was sold out to merchants by his brothers for 20 pieces of silver. In selling out their friends or relatives for money, all them were despising their birthright. After the deadly wound is healed and the beast becomes the "red" dragon, the Antichrist will make war against the saints and overcome them.
At the same time the deadly wound is healed and the beast of Rev. 13:1-2 becomes the red dragon, a voice from heaven declares:
And I heard a voice from heaven saying unto me, Write, Blessed are the dead which die in the Lord from henceforth: Yea, saith the Spirit, that they may rest from their labours; and their works do follow them. (Rev. 14:13)
Then the antichrist becomes the eighth at that point in time. The antichrist is the eighth, but he is also of the seven (or belongs to the seven). So how do we reconcile that?
The color "red" is the symbolic distinction between the beast of Rev. 13:1-2 and the great red dragon or scarlet-colored beast. While Satan certainly gives the Antichrist his power and authority when the ac is first revealed, he does not yet literally indwell him. This indwelling occurs when the deadly wound is healed. The color "red" is the distinction. Red or Scarlet-colored = Satan. The same way that Jesus revealed Judas to John (his most beloved) before Judas was indwelled by Satan, Jesus will reveal the Antichrist to the church of Philadelphia (brotherly love) before the great tribulation begins.
The asassination thing is pretty popular and there might be some truth to it, but I think there is something larger there because "one of the heads" would be interpreted as one of the mountains, which I believe refers to a kingdom or empire.
In my opinion it's all going to go down the same way it went down with Herod after he was "fatally wounded' from the sword of an angel in Acts 12:23. Herod bred worms and died. The same thing happened to Nebuchadnezzar when he was struck dumb for seven years after he failed to give God the glory for his power. It will be no different with the Antichrist. First he will put himself in the place of God (not necessarily standing in a literal temple), will refuse to give God the glory, and will then be struck down by an angel of the Lord. My opinion is that it will likely arrive in the form of a fatal disease.