Isekai Leveling

You know why some Isekai characters are OP in their own legends? Because they have to won the right to get isekaid. In their previous world, apocalypse will turn their world into a game. And they have to earn the #1 spot lest they become trapped in this endless cycle. This is Seo Lee's journey. Will it be a tragedy? P.S. Their memories of the game will be erased. But their cheats will remain.