Reborn as Mew: There's Something Weird About These Pokémon

Mengxing traveled through time and came to the world of Pokémon, and actually became the ancestor of Pokémon, Mew, but why are the Pokémon in this world so weird? Mengxing saw Charmander digging Squirtle out of the shell, his flesh and blood being torn apart, and Squirtle's blood splattering all over the ground. Mengxing just watched Charmander eat Squirtle one by one. I even saw a giant pincer mantis, which used its huge pincers to forcefully cut off its trainer's head, causing blood to flow from it. Is this scene really the world of Pokémon? Mengxing recalled that ball of light entrusting herself to save the world, but what on earth was she going to do? What needs to be done? And... What is happening in this world?