This passage is about the enforcement of imperial worship and/or totalitarian regimes in John’s time, an even more evil emperor yet to come, and about their forms of deception. (Remember, Revelation is also a letter to the Seven Churches facing current problems then as well as fulfillment of things yet to come.) This theme of allegiance continues today; whom will we serve and trust? Will it be good or evil? The chief ends of the beasts and Satan are to get people to worship them—or anything else besides the One True God. He will counterfeit the claims and ways of Christ by twisting them for evil purposes.
This is more about our battle against evil, Satan, and those who follow who are duped or have the desire to be evil than it is about a singular antichrist personality that may or may not come into existence. There are countless speculations on the mark and the number 666. In word meaning, context, and as a metaphor, the mark denotes ownership and control. The 666 denotes a parody or cryptic metaphor for Nero or anyone opposing Christ. Most of what is going on in chapter 13 is an explanation about what is going on in his time period. The proverbial 666 has been made into incredible magnitude by movies and sensational pastors who preach by their personality and ignorance and not out of the Scriptures. This makes good movies but not good biblical interpretation.
Basically, symbols in Revelation had specific meanings for a First Century Jew or Greek, like when we might say “it is raining cat and dogs.” These are metaphors not to be taken literally or lightly but should be taken as they meant then, not compared to a modern day newspaper. John was in a totalitarian, evil regime under Emperor Nero (as was Domitian) who was very much an antichrist (this means one who opposes Christ—not just one person but anyone who oppresses someone away from Him – 1 John 2:18, 22; 4:3; 2 John 1:7). This can also mean Nero and/or someone like a Hitler, a Mussolini, a Saddam Hussein, or someone who is yet to come). We are called, as Christians, to be watchful; however, it is foolish to seek an antichrist, predict one, or come up with some kind of fanatical theory such as a computer chip planted in us. There have been many theories; none of them have come true, and there is still an antichrist to come into fruition. When he does come, there will be no mistake of his identity.