We assign rarities with a couple factors in mind. Complexity, archetype, and card type variety are a couple. We don't necessarily want the Epic cards to be more powerful than the Commons or Rares, because they're harder to acquire. Generally Epic cards are higher complexity, but it's not a hard and fast rule. And we work within the parameters of a single class, so these 2 cards wouldn't have necessarily been compared directly.
Cora
We assign rarities with a couple factors in mind. Complexity, archetype, and card type variety are a couple. We don't necessarily want the Epic cards to be more powerful than the Commons or Rares, because they're harder to acquire. Generally Epic cards are higher complexity, but it's not a hard and fast rule. And we work within the parameters of a single class, so these 2 cards wouldn't have necessarily been compared directly.