You'd think we'd have come across it before if it was an ability. Plus lots of pokemon have more than one ability they can have at birth, but it seems like dragon moves can't hit any of these guys.
I guess they could be part ice, but even and ice pokemon would be at least a little affected, especially at my dragons' levels.
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I guess they could be part ice, but even and ice pokemon would be at least a little affected, especially at my dragons' levels.