Maybe a Fake Gintama - Chapter 4: [Samurai] and [Bushido]

Struck down amid the battle, the Hero and Demon King meet their demise. As their souls linger on the edge of the afterlife, a mysterious force intervenes, merging their fragmented souls together with a new being. Rusty, the living armor, now affected by their memories and presence, embarks on his own quest. Will he seek revenge on those who betrayed the hero, or will he fulfill the desires of the fallen demon king? or instead, forge his own path?

Yuki, a high school junior, dies heroically saving a stranger and is reincarnated in a fantasy world, where he discovers an extraordinary and unrivaled power.

It was just a normal morning but it was unknown to many that the apocalypse already started.

The origin was not determined but the infected started to appear after a cosmic event happened just outside of the Earth’s atmosphere.

The people and animals turned into man-eating mutants and zombies while some of the lucky ones gained superhuman abilities. Every living creature that had not “turned” started to evolve as the whole world was affected by the Mutagen.

However, it seemed that Earth also had its hidden side that humans would discover in a very uncanny way.

And was Mutagen the last of it?

Unfortunately, not.

Follow Mark, an Otaku, a Gamer, and a Shut-in that got trapped in the middle of the apocalypse due to an uncanny reason. Using his unconventional thinking, knowledge, and abilities, how far can he go in surviving the apocalypse filled with zombies, mutated beings, and dangerous people as a survivor in a world that was changing for the worse.

The labyrinth that swallowed humanity. Four choices were given to them.

Easy Mode, where anyone can survive. Normal Mode, where only those who fight survive. Hard Mode, where only 1% can survive. And the Solo Mode, where only one person survived.

The strongest returnee of humanity, Kang Taesan, was an Easy Mode player.

He heard countless times,

“What if you had chosen the Hard Mode, or even the Normal Mode?”

Regretting his cowardly choice while dying amidst destruction, he gets another chance to choose.

“This time, I won’t make the wrong choice.”

The strongest Easy Mode player has returned.