The why is that cabal outers are race "cabal" and not, in this case, Nightwalker.Searing Ward does a lot of damage, lasts a very long time and doesn't require the shaman to be present. I'm not keen on that powerful of an ability being a remote "I win" button against cabal outers, so I'm going to say that for now we're cool having outers be immune to SW. Sorry!
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