Drug-Eating Genius Mage is a Manga/Manhwa/Manhua in english language, Action Adventure series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.cc fastest updating comic site. The Summary is

[By the studio that brought you and !] Having reached his talent limit on magic, the protagonist was sent to the gaming world as punishment — to a huge city named Valkan. In order to survive, he builds relationships with other people and investigates the secret behind the “closed world”, striving to prevent the end of the world.