The Most Powerful Bodyguard - Chapter 1: How Much Will It Cost to Kiss You?

When a fantasy kingdom needs heroes, they skip the high schoolers and summon hardened Delta Force operators.Lieutenant Cole Mercer and his team are no strangers to sacrifice. After all, what are four men compared to millions of lives saved from a nuclear disaster? But as they make their last stand against insurgents, they’re unexpectedly pulled into another world—one on the brink of a demonic incursion.Thrust into Tenria's realm of magic and steam engines, Cole discovers a power beyond anything he'd imagined: magic—a way to finally win without sacrifice, a power fantasy made real by ancient mana and perfected by modern science.But his new world might not be so different from the old one, and the stakes remain the same: there are people who depend on him more than ever; people he might not be able to save. Cole and his team are but men, facing unimaginable odds. Even so, they may yet prove history's truth: that, at their core, the greatest heroes are always just human.

Back to the end of Ming Dynasty, he was reduced to a slave.

This emperor, a beggar can do it, a slave can do it, a bandit can do it, but a house slave can’t do it?

- Description from novelbuddy

Coincidentally, indoorsy-guy Zhang Yang went to the cultivation world, being the lowest level of zombie. By using a manual book named: “ Tai Yin Refining Figures”, Zhang Yang find his own way to success and leaves a “If a zombie knows how to use a manual, nobody can stop it “ legend in the world.

- Description from Novelupdates

In a world of endless star fields and interdimensional wars, the wizards' floating city conquered one world after another.At the wizard academy, through blood-stained exams, the towering wizard tower sent wizards batch after batch.Becoming an apprentice wizard, Richard activated the miracle furnace deep within his soul, where constant refining of materials granted him knowledge and skills...The veteran's weapon could be refined into legendary martial arts techniques.The ancient wizard's encrypted notes could be refined into lost knowledge.The remains of brutal monsters could be refined into monster bloodlines.In this era of great voyages in the wizarding world, Richard was destined to become a leader of his time.