The Abandoned Son Becomes the Mecha King

Abandoned as a child, Kayn grew up in the slums as a mecha prodigy. After finding a mysterious cube holding the key to humanity's fate, he rises from a scrap-metal mecha to crush the arena, beat his adoptive rival, and confront the father who never accepted him. When insect swarms invade, he pilots the Titan to end the war and lead humanity.