Doomsday Mechs: Starting with a Manufacturing Army

[Flesh and blood are weak, machinery ascends] + [Biopunk] + [Apocalyptic disaster] + [Mass production of troops] + [No harem]
As the apocalypse arrives, supernatural abilities, rampant zombies, biological mutations, and extreme natural disasters are constantly destroying humanity's hope.
As an ordinary robotics engineer without any special advantages.
Jiang Yi stood on the rooftop, gently adjusting his glasses. The cold, gleaming metal and the flesh of his arm blended perfectly together.
When cold weapons of war are imbued with the elegance of human flesh and blood, all the madness of the apocalypse seems so pale and powerless.
Under the distant setting sun, mutated creatures surged in like a tsunami.
Jiang Yi's voice was icy, and there was not a trace of fear in his dark eyes.
"There's only one thing we need to do, and that's survive."