Become a Summoned Beast 300 Million Years Ago

Folks, the data is all over the place. I won't update here anymore~ I'll see you in the next book if I have the chance! Xu Xian is an ordinary person who travels to a strange country of snake people 300 million years ago. He meets a snake girl who calls him the summoned beast she bought. Is he willing to be her Pikachu, or is he willing to create his own era in that world alone? But things were far from that simple. From the moment he came to the other world, the gears of fate had already begun to turn. What happened next was far beyond his imagination... How did life come into being, why did civilization rise, and why did it end? Why is there so much desolation everywhere in the universe? Everything is answered from here.