Douluo: The Asura Demon Dragon

On a land strewn with corpses, the sky was blood-red, and the air was thick with the stench of death. Deep within this land, a colossal black-and-red dragon was imprisoned amid heaps of massive iron chains. Its name was the Asura Demon Dragon, the emperor of the Asura Clan in ancient times and the strongest being in the Three Realms. Unexpectedly, it was gravely wounded in its battle against the Primordial Ancestral Dragon. Though it won, ancient gods seized the chance to ambush it and seal it here. Now, the ancient gods are all dead, and the seal is weakening. Our male protagonist transmigrates and becomes the dragon. What will happen next?