He has the power of separation, which in the early years he used to amplify his swordsmanship. He became known as the Scared Hero, then the Hero of a thousand flame, later still, the leader of the red wing military. A hero, became a dictator. His friends would turn against him, they would claim they were trying to save him from his own ambitions. But it was up to him to save the world, to change the world, because if his friends would turn against him, how could he ever trust that anyone would be willing to sacrifice their humanity for the betterment of the world, if he would not be the one to carry that mantle.
His scar was from one of his early battles, as a child, where he attempted to stand up to a knight known as a hero, who was doing wrong. Despite being a child, he managed to dispatch the knight.
He has the ability, the cut away a person's ability to 'do' certain things. He has cut away his own ability to harm his friends.
He seeks to change the world, to make it a better place.