Is there any recommendation for a novel about the protagonist's rebirth to the world that became a game five years ago? At the beginning of the story, the protagonist was still in school. Would there be a plot where he would fight monsters to unlock the map?

I recommend [Summoning of Elements in Online Games] to you! The main character, Li Hei, returned to the online game world five years ago. He killed monsters in the game to unlock the map, earned money to explore the secrets of the game, and became the top player in the game. This novel was full of game elements. The protagonist's rebirth allowed him to use the game knowledge of his previous life to gain an advantage. The seemingly ordinary but challenging elements such as the monster fighting map were also very attractive. I hope you like my recommendation. Muah ~