They're not, though. They have a low appeal. They're two of the least played races in the game if you discount allied races.
And Hearthstone is not a metric for anything considering it has "lich Jaina", "death knight Uther" and "Ragnaros the Light Lord". Hearthstone thrives on the silly, nonsensical and noncanon.
It's not, though.What a weird conundrum huh?
By that same logic: mark my words. Tinker class is not going to happen.Mark my words. Tinker class is going to happen.
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Except, unlike gnomes and goblins, dragons are a popular concept within WoW's player base, and being able to play as a race that is "next best thing" to a dragon has its own appeal on paper. Only time will tell if dracthyr will be popular or not.