From Abyssal Invasion to Bursting Stars with a Single Sword - Chapter 220 - 180: The Scientist Who Studied Demons

Sometimes dying isn’t even the worst part of your dayMark has been reincarnated into a dead town in a bog, one that has been recently destroyed and occupied by ravenous undead. They disappear every day and return again at night, mindless and hungry, hunting for any survivors. He’ll need to use cunning and subterfuge to avoid them, because since he was transported into the body of a child, he can’t level up. At least not yet.Bog Standard. It means “totally normal”, right? But for the small towns found in these bogs, there's no quick rescue and not much trade. Everything has to be made to last. To them, it means “excellent quality”. Mark will have to prove he's Bog Standard if he hopes to survive.This is an Isekai of excellent quality. It’s a progression fantasy set in a LitRPG world, rags to riches with an eventual OP main character. The pacing is slow-burn, incremental progression, sometimes slice-of-life, punctuated by moments of intense violence and possibly traumatic content.

Su Yao passed through and traveled to the Marvel world to become a mutant. He was still in the experimental base. He expressed a little panic…

Fortunately, at the critical moment, the mutant ability ‘imitation’ was awakened to imitate the opponent’s ability!
…
Imitation object→Orochi (title: Sun God, Will of the Earth)
Imitation object→Wanda (title: Scarlet Witch, owner of chaos magic)
Imitation object → Sun God…
…
Professor X: “We must find him as soon as possible and guide him to control his power to avoid causing irreparable disasters!”
Magneto: “You are my child???”
Thor: “Brother?”
Loki: “?”

- Description from novelbuddy

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!

Finding himself in an Last Airbender without an airbender around, a transmigrator waterbender goes on an adventure to stop the worst from happening to him.