You do know that "all" death knights did not get Frostmourne, right? Also, Jaina did get the Storm-Stave of Antonidas at some point. By your logic, all humans should have storm powers.
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"Hilarious leap".
Also says this in the exact same thread barely five hours ago:
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And yet the mechanic already existed in the form of the Enhancement Shaman's Ascendance talent, which is exactly what you said it did "remaining in shapeshift form temporarily", and on top of that, it does exactly what the metamorphosis from WC3 did: transformed the character from a melee to a ranged character.