Simple man with his overpowered army

A man played an immersive game that he started playing thanks to his brother. With his brothers help, he got an overpowered build on his character. Unfortunately, his brother died and he stopped playing the game alltogether because it reminded him of his brother.
One day he hears that the game is about to get shut down, and he goes there to say farewell to the thing he and his brother spent so much time on. But when the moment where he was supposed to be logged out, he finds himself still in his character. Strangely the NPCs start talking more freely and that the capital city where they were on was suddenly in a strange forest.
What will he do in this new environment? What kind of people will he meet?

(Note that the setting starts kind of like Overlord, the anime/novel)