Just before the new Diablo reveal, Blizzard announced a new card set for Hearthstone at Blizzcon, Rastakhan?s Rumble. The new keyword of the set is “Overkill," which allows you to attack with a weapon multiple times if you do more damage than is necessary to kill a minion. This synergizes with new cards that have triggers based on weapon attacks. In addition, each class is getting their own “spirit" cards, all of which are 0/3 minions that have stealth for one turn.
Details are few and far between right now, but the weekend is going to be packed with panels and in-person demos which explore the new mechanics of Rastakhan?s Rumble. So, we’ll have a bunch more on the new set throughout the weekend, and for everyone else… You’ll be able to play Rastakhan?s Rumble when it launches on December 4th.

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