My Muscle System in the Mage World - Chapter 3: Muscle System (1)

Having a rough life growing up, Wang Tong had numerous dreams of living a better life. However, his alcoholic foster father sells him off as a space settler of the distant planet Norton for some pocket change. Soon after his arrival, the Zergs overran the planet and obliterated its defenses in a matter of minutes. What awaited Tong on Norton was more than just an unbearable environment – its gravity alone was five-times stronger than earth – there were also swarms of bugs, constant hunger, thirst, and desolation.

While he lives a year of total carnage and survival, humanity’s Confederation eventually overcomes the Zergs on Norton and the powerful survivor Wang Tong is given a recommendation to a once famous, but now dying military academy where he begins his life anew.

Suzuki, an adult programmer, suddenly notices that he’s been thrown into a different world while wearing a casual clothes at level 1. He gained high levels and treasures after using the 3 times use-disposable-magic, Meteor Shower, once. After that he intends to do different world “sightseeing tours”? He meets 3 beast girls, beautiful purple and black haired sisters, and an eccentric blonde haired elf girl along with various people during his trip. Although there are occasional fighting with demons and demon lords, this is a heartwarming fantasy story at heart.

One day, Luo Jian woke up from his sleep and found himself in a locked chamber where the door and window were all sealed. A note with a few lines written on it was tacked to the wall: “Escape from this room within an hour, otherwise, you will die.”

There is a sequel called Reincarnation Night (轮回之夜) that takes place in the same universe but has different main characters

- Description from Novelupdates

When I woke up after a pretty crappy death, what greeted me was one of those famous fantasy worlds! I didn’t expect anything like becoming the strongest with a common job, or rising to the top with the weakest class…All I wanted was to live a slow farming life, but the world just wouldn’t leave me alone! And so I equally backstabbed good people and bad people alike, becoming a villain with a true sense of equality and just when I was about to retire and enjoy a proper life on a farm…“Master!”My former disciple at the evil organisation, currently the hero of justice came looking for me. Can’t you all just leave me alone?