I recommend the book "Dragon Tooth of Doomsday" to you. The plot is highly consistent with the information provided. In the novel, a huge spaceship suddenly landed on Earth, and alien creatures rushed out and killed all kinds of life forms. The weapons on Earth had no effect on the alien creatures. The protagonist was trapped in a spaceship. He thought he was playing a highly realistic game until one day he realized that the NPCs he killed in the game were all living humans from another planet. I hope you like this novel. Muah ~