I Never Run Out of Mana - Chapter 149: Butterfly Effect

The idiot Long Gen pretends to be a pig and eats a tiger, takes advantage of the girls in the village, travels across the countryside and forests, monopolizes the beauty and coquettishness, and achieves the legend of “Dragon Gen”. There is a widow in front of the door leaning on the door to watch, and a sister-in-law next door looking through the screen window… This book is determined to be a stallion, with the goal of pushing down and being pushed.

- Description from novelbuddy

After crossing over into a world of magic, Dean Bruce was mistaken for a powerful sorcerer. Though he initially intended to sternly refuse the beautiful woman’s request to become her mentor, she offered him far too much to say no!Completely clueless about magic, Dean Bruce had no choice but to make up spells on the spot. However, when he saw the astonishing power unleashed by the beautiful woman after chanting his random incantations, he was stunned.The spells he had carelessly invented… could they really comprehend magic and even forbidden spells?As Dean Bruce ascended to the pinnacle of magical prowess and became the Archmage, he candidly answered a reporter's question during an interview with the Alliance: “ never understood magic. I just made up a few incantations, that's all.”People were in awe of him—this, they believed, was the true humility of a Grand Archmage!

When an S-class elite assassin-raised captain of a special ops suicide squad comes home from a high-stakes Africa mission, he finds himself offered something that could potentially set him up for life- a curious assignment that he could use to finally exit his days of war and slaughter.

Then placed into a high-school setting, Lin Yi is tasked by the chairman of a top-tier multi-billion company with bodyguard duty for non-other than his own daughter, a certain little Miss of said high-school.

His enemies, once ranging from drug lords, mafia bosses, political figures, and national leaders, are soon replaced with spoiled kids who happen to have rich papas and mamas, and Lin Yi finds his intense expertise and high-threat skillset misused, and very underwhelmed…

But he does get a harem cast as diverse as his old enemies, so Lin Yi decides that, for the sake of messing around with girls as an invincible entity in a down-leveled environment, leaving his bloody and death-filled war days behind is something he’d definitely want to strive for.

- Description from Novelupdates

The empire has turned into the land of the undead due to a spell gone wrong. God summoned heroes from countless worlds to purify the empire and plant new hope. Lee Shin Woo, an ordinary earthling, was also summoned. As an undead, that is.