The novel I'm looking for is about a person from earth who is transported to another world with the powers of a player e.g. system, missions getting stronger by killing monsters and the like. After 5 years in this world the person defeats the final boss who has ice powers and his final mission is to go through a portal or a passageway which leads him to another world where those strong enough get transmitted and a normal goblin has about the same amount of power as him. In this worl players are treated as trash as they have no talent compared to the other inhabitants. And the MC final goal is to return home.