MTL - First Day In Game, I Got Ten Billion From Infinite Number Of Check-ins - Chapter 549 solve

Within the virtual world of “Avalon Online”, Finn, or otherwise known as “Echo” within the game, was one of its greatest players. After logging off from a long session, however, he notices something awry outside of his apartment.The streets were flooded with chaos, screams echo through the night, and hell is loot loose. Monsters from Avalon Online are running through the streets, wrecking havoc. In the midst of this hellish awakening, Finn is greeted with the one gift bestowed to humanity in this dark hour:[...Assessing life experience…][Assessment Complete][Name: Finn Thorne][Age: 20][Designated Class: Assassin][Starting Level: 5][A [Legacy System] has been bestowed to you for your accomplishments within Avalon.][Assimilation System Awakened.]In this twisted turn, as the world as it was once known is gone with the arrival of magic and monsters, the remnants of humanity must level up if they wish to survive.Finn is left in this dark, hopeless apocalypse, using his own experience from Avalon Online to best survive what seems to be an impossible task.

Yo, Hi! I’m Frank, I made a deal with a demon to pay me some money for receiving a guest for a few days every week.
I had no idea about what I have done.
On May 1st, Conan ‘the God of Death’ came to my house. I was forced to let him in and we get involved in a criminal case.
On May 8th, Bruce Wayne ‘Batman’ came to me. I was forced to follow him to fight crime.
On May 16th, Hannibal Lecter, The Silence of the Lambs, came to my home. I can only say that I really can’t stand my guests.

- Description from Novelupdates

In the near future, a space channel connecting the other world suddenly appeared on Blue Star, and a large number of other world monsters poured into the homeland where human beings depended for survival.

Human civilization has shrunk sharply and had to hide in the base city to survive.

Only warriors can lead human beings to open up living space and regain lost land.

However, martial arts requires talent, and not everyone can become a martial artist.

People with outstanding martial arts talent can not only advance quickly and break through limits, but also optimize their exercises and benefit future generations, and are admired by all mankind.

By chance, Lu Heng discovered that his martial arts talent could continue to evolve…

- Description from novelbuddy

After getting shot, Lucas, a serial killer, reincarnated into the novel world as a tragic villain with the same name, Lucas Ciffer.

Lucas Ciffer was supposed to be the Holy Kingdom's successor to the throne, but his demonic appearance and the powers he possessed terrified the entire kingdom. A white-haired boy with red eyes and pale skin, together with his dark powers, got persecuted and exiled by his own family. Not to mention that in the future he was destined to die by the hand of the hero.

Lucas fell from holiness, and, with the serial killer's bloodlust and knowledge of the future, he decided to prove the world right.

Yes. I could be a villain; no, in fact, I WILL BE THE VILLAIN.