Alloy Star Yu Zhan Ji

Story background Human urban civilization is highly developed on the surface, but there is a vast alloy-constructed alien world stretching underground. The cracks in the rock formations are filled with entrances and exits connecting reality and the alloy alien world. Various metal life forms and giant alloy behemoths are born in other worlds. Once they emerge from the ground in large numbers, surface urban buildings and power systems will be corroded and damaged by the alloy bodies. In order to resist threats from other worlds, mankind has established an exclusive defense agency, the Alloy Barrier Agency. Executive Officer Kurosawa has full authority to connect core combat forces and coordinate combat deployments. Kamisaka Yao and Lin En are the guardians of the earth carefully selected by the Barrier Agency, and they are also top "alien travelers". They each have tailor-made individual alloy mechas. They were ordinary students of Xicheng High School, and no teachers or students around them knew the secret identities of their guardians. Whenever the alloy behemoth breaks through the cracks in the rock formations to the surface, the two of them follow the instructions of Executive Officer Kurosawa and attack quickly to clear out the incoming monsters and seal the expanding cross-border holes in time. In surface defense operations one after another, the team slowly collected scattered clues, gradually uncovering the ultimate truth about the birth of the alloy alien world, and as young guardians, protected the entire human civilization on the surface.