Sending the Groom to Jail on My Ex-Girlfriend’s Wedding - Chapter 28: Good Heavens, the Iron Hammer Reappears!_1

A teenager who unexpectedly gets transported to the modern world from ‘the world of the immortals’ . He finds himself in the body of an ordinary guy. He wants to go back to his world and for that, he will have to practice to get stronger and investigate the reason why and how he crossed through to this world.

- Description from Novelupdates

At first, when he learned that he was forced to go to many different routine worlds and be reborn into all kinds of cannon fodder, he was against it.

Video game streamer Jing Yu, momentarily misstepped, and found himself in a strange professional gaming team.

Solo laner: Even if I have my eyes closed, asleep, dreaming, I can still kill you all!

Mid laner: Retreat? Not going to happen. Even if I only have one drop of blood left, I’m going to kill you all!

Marksman: Attack range advantage? I like to battle close-range! If you aren’t a coward then don’t run, let me kill you all!

Support: Support? As if! Wait until I switch to an AD build, then I’m going to kill you all!

Jing Yu: ……

Jing Yu: All of you, retreat! I’ll be the one to kill them!

- Description from Novelupdates

One day, I woke up only find out that I’d become a Demon Lord, an individual responsible for protecting a dungeon. The world I’d been spirited away to was one filled with violence. Gigantic monsters wandered through it and competed with each other each and every day for the right to survive. I had no choice but to strengthen my dungeon’s defenses in hopes of living another day—or at least that was what I’d thought. For some odd reason, I instead ended up spending my days in relaxation and bliss.