Shinwa Densetsu no Eiyuu no Isekaitan - Volume 7, Chapter 5 – Despair That Crawls Out of the Darkness, Part 1

After transmigrating into the Marvel-DC multiverse, he, once an ordinary person, has now become a world-renowned mercenary and assassin.Things have changed. Should he become a righteous hero, or continue his dark profession?“Don't use such shallow concepts like good and evil to judge me. I only do what I want.”Suddenly, the protagonist appeared behind the author of this synopsis, punched him, and sent him flying.“The truth is simple. I am the death knell that rings in everyone's ears!”

You are the ruler, I am a subject, you want loyalty, I’ll give you loyalty. You are the ruler, I am the subject, you want my sacrifice, I will sacrifice for you. This lifetime, we’ll only be ruler and subject…… cannot become the one who accompanies you to experience everything.

A deposed empress, a failure of a substitute. Charging into battle, he was the emperor, and she, his general. But within the intimacy of their military tent, he was her husband, and she, his wife.

But everything was star-crossed. For the one he loved the most, he would push her into hell again and again.

- Description from Novelupdates

“Primum non nocere.”

I accidentally changed the whole world, the resurrection of the dead, genetic variation, recovery of the qi, mountain and seas reborn, land and seas expanded and evil spirits have started to appear.

Ghosts are now commonplace. Some people now have three heads and six arms. Some people have obtained martial arts techniques and ordinary people are now just cannon fodder.

Fortunately, I have acquired an ability which can make various items mutate.

books into martial arts or cultivation manuals,

fruits into precious treasures of heaven and earth or poison that you can only imagine and…

weapons, that can split the earth or gain sentience!

- Description from Novelupdates