I wonder if the old "child of Light and Shadow" prophecy by Xe'ra will involve Arator in the Worldsoul Saga.
Alleria is super relevant in War Within, and I bet Turalyon's role will be massive in Midnight. Maybe Alleria does succumb to the Void, or die resisting it. Then Turalyon dies trying to save her or something. Perhaps she inadvertently kills him in a moment of rage and confusion. As a way to gain the trust of Xal'atath perhaps.
Then Arator comes along to save the day.