<p>Is he really gone Raava did said that one can not completely destroy the other and beside were there is light there will always be shadow and vise versa ,so were there is darkness and chaos you can bet Vaatu wont be too far behind
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<p>Strictly speaking, I don't think he was destroyed, just purified. My guess is that his dark nature will creep back after a few millennia as he wanders the Spirit World, as opposed to erupting out of Korra like a xenomorph chestburster.
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