Mechanics, Mutations and Powers

This is an epic story of struggling to survive in the torrent of metal ruins and flesh and blood. In 2150, a meteorite fell in the Antarctic, and mankind's nightmare began. A strange and powerful creature appeared from the Antarctic of the earth, defeating mankind steadily. After 50 years, humans have retreated to the roof of the world, the capital of Terra. This century is known as the Scarlet Era Duan Yi, an amnesiac engineer, woke up from the cold metal ruins with half of his body paralyzed. Repair tools, repair prosthetic bodies, repair order, and repair the world step by step in the ruins But what is the price and purpose of all this?