Other people transmigrate with a System. I transmigrated with nothing but the Wilderness Survival Handbook, and an ordinary mortal body that could be torn apart by higher-dimensional radiation at any moment. The laws of nature collapsed, magic stopped working, higher-dimensional gods treated me like an insect, and abyssal beasts roared beneath the earth.
I brushed the dirt off my hands:
Water pollution? Purify it with physics and teach the magic tribes what science means!
The whole tribe is infertile? Use biology to help them put food on the table!
A god is attacking from a higher dimension? Sorry, rule number one of wilderness survival: use everything at your disposal to strike back!
I even picked up an alien tyrant with the highest combat power around. I went from being a mere mortal he used as a translator to ordering him to dig irrigation ditches, chop wood, and make pottery.
He could crush a continent with a flick of his finger, yet I had him farming in the fields. "Mortal, just you wait!" Me: Just wait and see how I use science to rebuild this new post-apocalyptic world!
(Hardcore science, a mortal's rise, an alien tyrant, and post-apocalyptic farming. Watch me use Earth's knowledge to take down the entire magical wasteland!)