How Can I, the Dark Son, Save the World?

In his previous life, Yuan Lai was the holy son of the Dark Church. Just when he thought he would spend his life carefree and happy, he learned that he was the villain in a book. So, with admirable optimism, he destroyed the world.

In this life, he was reborn into an ordinary farming family. His original self was an orphan raised on meals from the villagers. After the whole village was massacred, he vowed revenge, but died before he could get it.

And so Yuan Lai took over and lived on in his place.

[The pacing may be a little fast + possibly some niche triggers]