It will be Kerrigan.Only one thing is certain; The Jailer is the final boss, and in his corruption, must be killed, but like "there must always be... a Lich King", I'm sure "there must always be a Jailer" to maintain the natural order. The million dollar question now is, who will Blizzard choose as the new Jailer? Bolvar, Sylvanas, or the dark horse, Arthas? From a narrative point, Arthas would be cool, as he'd be the new Jailer of the Dead while Illidan is now Sargeras' jailer. Keeps the door open to re-visit two very popular characters any time they wish to dabble in the stories of Fel and Death. Bolvar should return to being Lich King, and Sylvanas should be thrown into The Maw to be tortured for all eternity. I just wrote the most satisfying ending to Shadowlands possibly imaginable.
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