I Pick Up Trash in the Apocalypse

After a cataclysm turns the world into a wasteland, a former Demon Sovereign must scavenge the ruins and rebuild his strength. He once had the power to destroy heaven and earth, and stood against a heroine of the final city who had risen to the brink of godhood. Their battle shakes the world, but countless thunderbolts suddenly fall from the sky, reducing the continent and the entire planet to an apocalyptic wasteland. When the male lead awakens, his cultivation has been cut in half, leaving him at the Foundation Establishment stage. With no other choice, he begins gathering what he can from the ruins and regaining his power step by step.