Rise of the Stay Abyss Overlord

"Xavier Grant's brother, Zane, steals his SSS-class mecha core, determined to become the world's hero. Little does he know that the core is actually bait, designed to lure in a catastrophic threat. Xavier turns the tables, choosing the F-class mecha that everyone mocks before being exiled to the Wasteland. There, he joins forces with three other outcasts who have been abandoned by society. Armed with the hidden treasure that has been severely underestimated, the four rise from the bottom to build the strongest team in the galaxy. When disaster sweeps across the Capitol, Zane is pushed to the brink, while his hypocritical family comes crashing down."