MTL - History’s Number 1 Founder - ~ 1316. When the World Dandao first

Naofumi Iwatani, an uncharismatic Otaku who spends his days on games and manga, suddenly finds himself summoned to a parallel universe! He discovers he is one of four heroes equipped with legendary weapons and tasked with saving the world from its prophesied destruction.

As the Shield Hero, the weakest of the heroes, all is not as it seems. Naofumi is soon alone, penniless, and betrayed. With no one to turn to, and nowhere to run, he is left with only his shield. Now, Naofumi must rise to become the legendary Shield Hero and save the world!

[You have transmigrated, named Gu Sheng, and are a farm boy.][This is a dynasty in chaos, where demons and monsters lurk and bandits run rampant; as someone at the bottom, you face hellish survival difficulties.][You decide to lay low.][You awaken a mastery panel.][You breathe a sigh of relief, you can start grinding.][You grind Chopping Wood to Perfect, chopping bones and breaking tendons with ease.][You grind archery to Perfect, becoming a godlike archer who can hit a louse at a hundred paces.][You learn the Iron Stone Fist, set foot on the path of a Martial Artist, and grind it to Perfect, with punches as heavy as a million pounds.]……[You learn the Longevity Eternal Youth True Art, greatly extending your lifespan, giving you more time to grind, and greater hope to lay low.]……[You grind to the limit, steadily laying low, and one day you suddenly realize, you are invincible.]

A good-for-nothing man married a beautiful girl but was kicked off the bed on the wedding night. Furiously, he wrote a bill of divorce and ran away.
He was schemed a car accident in which he nearly lost his life. However, it turned out to be a blessing. He swallowed the soul that passed through the outer world, thus obtained superb medical skills and martial arts.
Later on, with the silver needles and invincible martial arts, he embarked on the road of counterattacks and was committed to his great dreams.

- Description from Novelupdates

Arthur, a Rich businessman was kidnapped and tortured for months by men his wife hired. After months of this hell, he was given a second chance, a new life in a different world and, of course, Arthur would rather start a new life than stay and continue to be tortured, so he accepted the deal that was proposed by a mysterious individual, but when he finally was reincarnated, Arthur discovered he was a..... parasite?