Knights of the Frozen Throne, the latest Hearthstone [Free] expansion, has been welcomed by players, but it looks like it also messed up Arena in a couple of ways. As reddit user adwcta pointed out, several of the new cards are currently missing from Arena. Iksar, aka game designer Dean Ayala, responded to that post and said that there are currently 12 cards missing from Arena. This is because of a bug that has been fixed internally and should be going live at sometime this week (if everything goes as planned). He explains that it all comes down to an editor bug that would make cards "undraftable." So, expect to have all the cards available in the Arena by the end of the week.
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The original poster also complained about the new move where Arena pushes "synergy picks" in the first two picks. The poster complains that the system isn't well implemented. Iksar again responded to this complaint and said the team is gathering feedback from reddit, the official forums, the best Arena players, and internally in an effort to see if the changes are working or whether they need to go back and fix things. If you're an Arena player, are you happy with the new synergy changes"

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