Or, gasp, the Naaru is looking to possess his body as he can hold such power and he controls him, or any other hundreds of possibilities other then 'LOL I KNOW WUT HAPPENS RUINED CHARACTER BLIZZ SUX!'
Where's the redemption?
Illidan in the past: Fighting to destroy the Burning Legion by any means needed.
Illidan in the present/future: Fighting to destroy the Burning Legion by any means needed.