The Game of the Greatest Black Mage - Chapter 7

An advertising director is reborn in 1988 Hollywood as an eighteen-year-old blond-haired westerner named Eric Williams.

From then on, he starts writing movie scripts and television songs, becomes skilled in directing every kind of film, wins over all kinds of female celebrities, and takes the road to become a Hollywood legend.

- Description from Novelupdates

Humanity was on the brink of destruction. Muyoung, an assassin from the Forest of Death, fell to his knees. There were corpses all around him. For years, he had worked for the Forest of Death and had finally been able to eradicate them. Now, he, himself, was about to die. He closed his eyes as he felt his heart stop beating.

I was reincarnated in a game-like otherworld.[ Warning! When acquiring an active skill, all stats will decrease by 80% for each active skill! ]...What the hell.