Hearthstone's "One Night in Karazhan" Adventure is coming tomorrow, but backlash over one card has already led to an unprecedented move.

The new Priest card "Purify" silences one of your own minions and draws a card for two mana. It was roundly criticized by the community and pro players upon its arrival, to the point that even presenter Dan "Frodan" Chou made a crack at its expense during the reveal stream he was hosting. Our own review called it the worst new card of the set, for being overcosted and too narrowly designed. Blizzard appears to have heard the outcry, as it has decided to remove the card from the Arena pool, keeping Priests from drafting it in the randomized mode.

The revelation came from a Designer Insights video with lead designer Ben Brode. Brode took a concilliatory tone, acknowledging that it's not a very competitive card, and saying that the team underestimated the community's view of Priest and probably would have presented it differently. The community had been very negative on Priest lately, and Blizzard holding all of its new cards for the last day of reveals made some hopeful that it would be receiving powerful new cards to help balance it more toward a real competitive edge.

Brode argued that in its playtesting, Team 5 found people had fun making a silence-based Priest deck. Sometimes cards aren't very competitive, he said, but they're put in the game because they allow for unique deck types that are just fun to play.

Still, though, Brode said that Arena balance is another animal. He said that the team is currently working on a solution to better determine how frequently a card appears in the Arena draft, but that would take some time. Until then, to prevent Purify from dilluting the Priest's already fairly weak card pool further, the team will simply keep it from appearing in the Arena draft at all. 

Blizzard has excluded cards from Arena before. When it released Whispers of the Old Gods, it opted to keep the various C'Thun buffing cards from appearing in the draft, since there were so many of them and they're poor on the whole unless you have C'Thun in your deck. But those were Neutral cards. This appears to be the first time that the Hearthstone team has specifically excluded one card from one class for the purpose to help make it more competitive.

For more on One Night in Karazhan, check out parts one, two, and four of our card reviews.