Mason is not imaginary, and neither is his world. He's not a ghost, but he does have incredible powers. Even though he's not a hallucination, his existence is still hard to believe. What Mason is, is the one Aerling capable of saving an entire world. Mason thought he was going home, but surviving Sentinel attacks and making it back to the Aerling world is only the beginning of Mason's fight to protect the ones he loves. Every Aerling believes he can save them, but in order to win a battle that has been raging for millennia, Mason must face down the one man he truly fears, the only man capable of withstanding his power. This is one fight Mason may not be able to win.