I think you need a mixture of both for a successful cube. The unfair decks can mitigate a Hero of Bladehold, but in the same sense Hero forces those unfair decks to put up or shut up, i.e. you either do your unfair ***** now or you die. I think it's possible to support the unfair strategies without having to force too many of the narrow cards that are great in these unfair strategies into your cube.
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