Maybe. But he specifically saw Anduin's holy abilities. Unless Anduin's just Warcraft Goku, which is a high doubt imo.
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That's...not what I meant. Maybe Sylvanas thinks this? But the Jailer only sees the Void as an obstacle towards Cosmic domination. He wants the entire WoW Cosmos to himself. That's it. Sylvanas is not getting a redemption arc though, I don't think. We already got Kerrigan in Legion, with Illidan. Look how that went.