The Terminally Ill Young Master is the Mad Dog of the Underworld - Chapter 103

As a promise, he went out into the world as an assassin. 3 years later, after becoming the Supreme Assassin, he gave up on everything he had and returned to the ranks of ordinary people. But one day, Kismet, a mystical game created by the National Research and Development had appeared.

Enigmatic hands, spectral frame, and one cunning strike just like the swing of the Grim Reaper. The Supreme Assassin takes on the mystical world, and how his legendary tales sets off, progressively ascending the altar to becoming the best.

- Description from Novelupdates

A man dies in a plane crash from a supposed terrorist attack. A mysterious... Devil reincarnates him into a new world and gender bends him into a female.

It looked to be your standard fantasy world at first, but as Arpious traverses farther into her journey, she finds out that she might not be on a planet.

She discovers many secrets that are unknown to her fellow monsters, through the help of her comrades, wives, and even enemies?

She learns that the sky is fake? There are worlds right under her world? How is that even possible?

Spirits instead of gods? Where the heck is she?

Yun is a novice MMO player who equipped only unpopular skills labelled as garbage. However, soon after the official launch of the game, the NPCs stopped selling Recovery Potions. Everyone finally started to notice the importance of Support Magic and Items. And that spells trouble for Yun as well as all the other support-based players. They received orders for recovery potion from endless flood of players en masse, some more aggressive players even go as far as forcing the support players to be their personal craftsman. In order to prevent this from going out of hands, all the support players grouped together to form a community to keep things in order.

An ordinary student, a wretched peeper, a cowardly teenager with a kind heart. In a terrorist attack, he inherited the knowledge of countless elites, embarked on a path of God Jagged Tu…

He is an artist!

He is a mathematician!

He is a psychology Doctor!

He is a master of fighting!

In fact, he is a man

Taken off raw site:

A wretched, dirty young man is working during the summer when he was caught up in a mysterious explosion. After that explosion, the young man is then left with the memories and knowledge of dozens of the world’s experts.

He has changed, his heart has become cold, iron-blooded. He became a killing machine, his mind turned mechanical, calculative. Everything goes according to his plans and calculations!

In this magical, slaughterous world, a door is opened for him…

- Description from Novelupdates