MTL - Low Temperature Dependence - Chapter 100

The story is about a a hitman, Who dies because of his own recklessness and transmigrates into a game he used to play after his retirement as a hitman.I'm not gonna spoil any further, but i might answer few of your questions.Is MC overpowered?Nope, he'll become strong over time and all battle he'll fight will be because of his effort and techniques.Is there magic and adventure?Yes! It have both magic like normal isekai with adventure and fighting with monsters and many other things. There are other important things like “Essence Stone” But let's talk about it in the chapters.There will be harem?Not really, He will be in contact with many beautiful female and males but one waifu but i haven't decided yet.All i can say is, give it a try, I'll try my best to make it worth your time.

The moment when mercenary leader Kwang Hwi receives video game like abilities, the world is suddenly thrown into chaos. A thick fog envelops the Earth, bringing with it savage, otherworldly monsters. At the same time humanity has been rendered defenseless against this onslaught, as the strange fog turns most weapons to rust. With mankind spiraling towards oblivion, it is up to Kwang Hwi, with his new abilities, to save the world. Watch as Kwang Hwi leads his militia and becomes the last bastion of humanity. Will he be this world’s savior, or its conqueror?

When gods gather, lightning will strike and the earth will move. Immortals! Which of the numerous way to immortality should one follow? Immortals are hard to seek, but why should immortals hide? Heaven has no mercy, but humans have emotions, and these emotions hinder the road to longevity!

Train the inner self to stay calm, train the external body to be resistant, then cross the three continents and four seas alone, and fight valiantly with demons and devils! With the heavenly baton in hand, raid the devils and demons without any resistance! Take one step to cross nine stars and chase the sword in the dreams! Traverse a thousand li of river and mountains in a single day! The exceptional beings do not mix with the ordinary! Within the universe, where can one find an obstacle! Moving like a dragon, with talent like a phoenix! The heavenly Daos and stars will guide one’s way!

- Description from Novelupdates

Reborn and returning, he possesses medical skills, can practice immortality, has a slave who is the king of killers, and a maid who is the school beauty pursued by everyone. Even casually taking out a piece of trash can shock the world. His return has set this world ablaze.