Turn over the Prehistoric World at the Beginning and Build a Mecha to Kill the God.

Spiritual energy revived. The new prehistoric world is coming, demons, demons, gods and gods are about to appear, and the human race will be destroyed! The god-level selection system appears: "Option one, the host alone has the information about the destruction of the world by the flood and the recovery from the prehistoric times. The host will become the last human being on Blue Star!" "Option two, the host will hand over the prehistoric world to the country, travel through time and space to recognize the master, the host's fate will be bound to the national destiny, and the host will be rewarded with the ability to build the God-Slaying Mecha!" The protagonist chooses to hand over to the ancient world and live and die with the country! Build cities on the water to cross floods, cast god-slaying mechas, and make people comparable to immortals! The human race will never be destroyed!