the Antichrist is not mentioned in the Quran but in the hadith, n all Christians n Jews will follow him, n so will all other kuffars Hindus/atheists/seculars/liberals/Buddhists .... and so will the majority of Muslims ( mostly women) except the true Muslims, n many of them will be stationed in modern day Syria .
but before he makes his rise, Muslims will indeed unite with Romans to fight a great battle against an unknown enemy, the Muslim-Roman alliance shall win, then the Romans betray the Muslims, n after 9 months they land north of Syria rising 12 flags (probably using the Turkish Air Base of Incirlik ), under each flag 12000 soldiers (960000 in total ), the battle is what christies call Armageddon, it lasts 4 days n 4 nights, 1/3 of the Muslim army runs away, 1/3 is killed , and the remaining one third wins the battle, after that Muslims conquer Istanbul for the second time (that means Istanbul is no longer under Islamic control before this great battle) , then they conquer Rome, and that's when the Antichrist comes out angry and does his thing until Jesus peace be upon him is granted permission to descend to earth , he kills the Antichrist and leads the army of Muslims to kill the very last Jew on earth (the Prophet SAW says even rocks and trees will speak n say :" Oh Muslim there is a Jew behind me come and kill him " ). after that another great tribulation starts, Gog and Magog r granted permission to come out, Jesus and the few Muslims with him hide in the Egyptian desert mountain of Towa while Gog and Magog kill all living organism on earth, Allah SWT then sends a worm from the sky to kill them all like one soul n also sends birds to take away their stinky bodies, n then it rains non stop until the earth is cleaned up from their smell, Jesus PBUH then comes down from the mountain and rules the earth for 40 years, gets married ... (continues his life from where he left it) .