Make this character a normal AU character. Which means you would change some canon information to make it so that he has his powers, and the blight at the same time. The previous game history would not be included - just a deviation of canon that makes him markedly different from canon either physically or in personality. (in this case, physically)
Option 2:
Stay true to the CRAU, which means including only circumstances and events that happened in the previous game. From what I understand this would mean no canon memories, and only abilities that he was able to use in the previous game.
Re: Revisions / Questions
Option 1:
Make this character a normal AU character. Which means you would change some canon information to make it so that he has his powers, and the blight at the same time. The previous game history would not be included - just a deviation of canon that makes him markedly different from canon either physically or in personality. (in this case, physically)
Option 2:
Stay true to the CRAU, which means including only circumstances and events that happened in the previous game. From what I understand this would mean no canon memories, and only abilities that he was able to use in the previous game.
Which would you prefer?