In 2031, during the Xianglong Crisis, Leon Lau found himself in the midst of chaos when the Quantum Reactor, a cutting-edge energy source, catastrophically malfunctioned. This event triggered a sudden global transformation where all living beings and machines underwent unique evolutions, leading to the emergence of the formidable B.R.A.I. entity. Humanity's existence was imperiled, compelling them to combat the B.R.A.I. using M.O.E.V. units. Seven years post-crisis, Leon resided on the outskirts of Neo Xianglong, a fortified city, with Chloe Lau, bound by a familial agreement. Together, they toiled to develop a solution against the relentless B.R.A.I. menace. Amidst their daily routine, plagued by the weight of the past, imminent dangers loomed on the horizon.