In 2031, the world goes through a drastic change after a next-generation quantum reactor fails catastrophically in an incident known as the "Xianglong Crisis."
The energy that springs forth from beneath the ground swallows up city buildings and covers the earth,
eventually leading to the emergence of new organisms called B.R.A.I. that are both organic and mechanical.
Seven years later, Xianglong has been reborn as the fortified city of Neo Xianglong.
It is the last bastion of hope for humanity against the rapidly evolving B.R.A.I. threat that has pushed mankind to the brink of extinction.
Leon, Chloe, Queenie and Doug are led by destiny to gather at Neo Xianglong.
Cecile, Cain, Jay and Gren welcome them into the defense force.
The special unit Pandora is born to fight for the survival of humanity.
The hope of everyone lies in their hands as they enlist.
The last remnants of mankind fight for survival against the B.R.A.I., an ever-evolving entity blurring the boundaries between lifeforms and A.I.
Leon's research proves effective as his newfound powers overwhelm a monstrous B.R.A.I., leading Cain to propose an alliance to protect the city.
Jay reluctantly orders Leon to continue his research on the unstable hyperdrive system in hopes of gaining a tactical advantage against the B.R.A.I.
Feeling responsible for the reactor accident, Leon offers to go to the frontline when a new type of B.R.A.I threatens to destroy the city.
When a cargo plane is destroyed by an unknown force, Leon suspects a flying bird-like B.R.A.I is to blame for its destruction.
Leon gets dressed up to head to the city, and Chloe follows him. She thinks he has a crush, but he's tracking a strange phenomenon.