It's my opinion that the entire zoo archetype needs nerfing to some degree. They are 95% guaranteed to have a strong opening with a good curve, whereas the opponent has a much lower chance to find the removal needed at the right times.
Blizzard must realize that this isn't MtG where you can actively choose to block things on your opponent's turn. Because there's no way to react during interactions, the power level (for low-cost minions especially) really has to be brought down.
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