There have been antchrists since NT times and I believe more to come. We know there are many enemies of Christianity. Watch the news.
"Dear children, this is the last hour; and as you have heard that the antichrist is coming, even now many antichrists have come. This is how we know it is the last hour" (1 John 2:18).
"Who is the liar? It is whoever denies that Jesus is the Christ. Such a person is the antichrist--denying the Father and the Son" (1 John 2:22).
Even some will declare they are Christ!
"For many will come in my name, claiming, 'I am the Messiah,' and will deceive many" (Mt. 24:5).
Strong's Concordance
antichristos: antichrist, (one who opposes Christ)
Original Word: ἀντίχριστος, ου, ὁ
Part of Speech: Noun, Masculine
Transliteration: antichristos
Phonetic Spelling: (an-tee'-khris-tos)
Definition: antichrist, (one who opposes Christ)
Usage: antichrist, either one who puts himself in the place of, or the enemy (opponent) of the Messiah.