Antichrist describes both people who are against Christ and those who pretend to be Christ. At the end of time, there will be a final antichrist who will lead persecution against those who are truly following Christ.
In Revelation chapter 18 an angel announces, “Babylon is Fallen”. The fall of “Christian” Babylon happened when Pagan Practices entered the Roman Catholic Church, resulting in False Doctrines and Practices. Many Denominations are uniting with Babylon today.