全クリア済みの俺、世界崩壊後も無双する

Leonard Miller nearly dies a dozen times completing every level of a mysterious game in closed beta. The moment he returns to the real world, the game goes live.On Earth, for everyone, whether they signed up or not. Dragged back in against his will, Leonard has one edge no other player does: he's already been through all of it. Armed with maxed-out attributes and complete knowledge of every trap and pattern, he tears through the stages, protects the people he loves, builds alliances, and slowly pieces together a chilling truth that a higher civilization has been using Earth as a playground. He intends to shut it down permanently.