Long ago before humans and devils emerged, there are two ancient races known as the Forerunner and the Nasods. Both boasted extreme technology which can overpower even God himself. In order to "keep the balance", God killed them off. What happens when the powers of both races falls in the hands of a normal looking human boy alongside a sealed gear? (This is a crossover between highschool dxd, halo, and elsword. If you have some things that you think can benefit me, please do comment!)