In the ruins of Cascadia, two centuries after civilization's fall, humanity clings to survival in the shadow of the relentless machines. Jin, a young resident of the Undercity, dreams of joining the engineers' caste. But when a fateful test failure thrusts him into the military, he finds himself on a perilous mission beyond the safety of the underground. What begins as a routine patrol ends with Jin's death - but his story doesn't end there. Caught between loyalty to the Undercity and the harsh realities of a world ruled by machines, Jin must navigate a new existence. Will Jin's journey lead him back to humanity's side, or will he forge his own path against the relentless tide of the SIGMA CORE's machines? In this gripping tale of man versus machine, Jin must confront his past, challenge his beliefs, and uncover the shocking truth about the world above – and the one he left behind.