Reincarnated as Karna in Asoiaf RKA

A common man received a strange questionnaire, asking him what sord of power he would like to get if he was reincarnated in the ASOIAF world with the mission of protecting the Rhoynars from the Valyrian empire.
Later, he lived a normal, but long and fulfilled life; complitaly forgotting about the formulary that he filled years before. After his death, to his surprise he reincarnated. It was then that the memories of the questionnaire striked him.
Embark on this tale, which mixes first-person and third-person narrative, about the appearance of a ASOIAF version of Karna, changing the world history and enjoying his life to the full of his abilities.