Damn, I Have to Marry the Strongest Antagonist at the Start? - Chapter 550 - 546-Together Forever

Cao Xin, a young man on earth, died in a car accident, traveled to a troubled world where supplies were scarce, and obtained a “Bronze Immortal Gate”…

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- Description from novelbuddy

Jiang Chen had unexpectedly found himself thrust into a world of cultivation, stepping into the role of a core disciple within a famed sect. Fated to be the villain, his future loomed with calamity. He had plotted against the protagonist, crippling his dantian and leaving him a disgraced outcast teetering on the edge of expulsion. Were it not for an unexpected twist, Jiang Chen’s part might have ended as a mere footnote in the protagonist’s glorious tale. Fully aware of his precarious position, Jiang Chen’s lips curled into a sly grin. Alone, he mused: ’Is the protagonist powerful? Without a doubt.’ ’But will I tremble in fear? Absolutely not.’ ’Why? Because I have the Immortal Great Villain System!’ ’Wait... there’s more than one protagonist?’ ’Well, isn’t that just perfect?’ With a determined glint in his eyes, Jiang Chen declared to himself, ’As the ultimate Great Villain, I will defy the will of Heaven and seize my place at the summit!’

What happens when a scientist from a futuristic world reincarnates in a World of Magic and Knights? An awesome MC is what happens! A scientist’s goal is to explore the secrets of the universe, and this is exactly what Leylin sets out to do when he is reincarnated. Dark, cold and calculating, he makes use of all his resources as he sets off on his adventures to meet his goal. Face? Who needs that… Hmmm… that guy seems too powerful for me to take on now… I better keep a low profile for now. You want me to help you? Sure… but what benefit can I get out of it? Nothing? Bye. Hmmm… that guy looks like he might cause me problems in the future. Should I let him off for now and let him grow into someone that can threaten me….. Nahhh. *kill*-

Alternative: Leylin is transported from an advanced technological era into a medieval world— except there’s magic. Equipped with “only” his quick wits and an A.I. chip fused to his soul, he sets out to become the most powerful magus the world has ever known. In a land divided into the Light and Dark Magi, the weak can either be cattle or disposable slaves. Only the strong can determine their lives, and only they have the luxury for virtue. Yet strength is only a tool for Leylin, like any other. His goal, in the end, is his own.

Humanity’s first 8th Class Mage.

Betrayed, he traveled back 30 years into the past.

The story follows Ian Page, archmage and the first man to break through the 6th class, then through the 7th and become the most powerful mage, an 8th class mage.

After a lifetime of war and killing, the continent was finally unified thanks to his efforts. Now, old, his wish is to live the rest of his life in peace and try to find salvation for all the blood he spilled. However, his old friend, maddened by paranoia, couldn’t tolerate someone so powerful, so he betrayed Ian and killed him.

In his last breath, he cast a time magic that allowed him to travel back to when he was a young boy. With all the knowledge he previously had, he decided to do things better so he could end with less regrets.