Quote from Blizzard

In the most recent patch, we discovered an issue where some players were unable to start a new Arena run. This particular issue is unable to be hotfixed and requires a client patch to resolve. The good news is, we’re about ready to patch Hearthstone and get those affected back to normal!



With that said, we’re not planning on too many additional patches between now and open beta, so we’ve also decided to take this opportunity to make a couple of changes to some Mage cards that utilize the Freeze mechanic.



We’ve been keeping an eye on Freeze mechanics for the past few months, and we’ve decided to make some changes to certain cards that utilize Freeze in this patch: Cone of Cold, Blizzard and Frost Nova. These cards are all having their mana costs increased by one. We understand that the Freeze mechanic can be frustrating to play against, and we feel that these changes should allow the opponent some additional time to be aggressive with their minions and well as slow the overall pacing of the control-based Mage play style while still keeping Freeze playable in many different types of decks.



As with all Expert card changes, Cone of Cold and Blizzard will both be disenchantable for their full value for two weeks starting from the day of the patch.



Thank you for continuing to test Hearthstone and giving us your feedback!