Strongest Being

Kai Strom a boy who is bullied and made fun of alot for not having power. His life isn't the greatest, but it's not the worst as he has a few friends even though his real family look down on him. Kai has been seeing this man that looks familiar, but why is he talking as about he is from the future. One day the city is attacked when he's out with his friends and they began to run away. They're attacked that's when the man reveals himself that he's from the future where he becomes the strongest Being and called a hero. At the cost of all the people he cares about and majority of the world. He came back to save the world from that fate. That's why he asks his future himself to give him the power to save it which he does. Now he must save the world from the fate that it has.