Harry Potter: Dimensional Wizard - Chapter 57: Second Philosopher's Stone In the World.

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

Lin Ke traversed to this world and, with the help of a system, utilized modern knowledge to farm and develop, claiming kingship and dominance.This is a world of professionals, a world of swords and magic, a world of bloodline inheritance, and a world of countless racial conflicts!One day, Lin Ke rode a bicycle with training wheels past the army, facing an endless enemy ahead.[Shield Warrior], [Arsonist], [Tree Shepherdess], [Wind Whisperer], [Thunder Sword Maiden], [Eternal Freeze Knight], [Voodoo Warlock]...Looking at the diverse group of followers behind him—tall, short, plump, thin, old, weak, sick, and disabled—Lin Ke laughed and raised his arm to call out: “[Workers]! Delivery [Knights]! [Scientists]! [Doctors]... Raise the flag of Azanen and charge with me!”Thus, amidst the eerie cries and howls of his followers, the history of the boundless planes was forever changed.

“Darling, I want…”

Follow Benjamin Joyce, an elderly man with a passion for blacksmithing who spent his life travelling the world and learning new things. Now, after helping out the developers of the first ever real VRMMO game, he gets the chance to play said game earlier than the majority of other people.