Blizzard community manager Aratil has confirmed that the first expansion for Hearthstone, Curse of Naxxramas, will be arriving in July. The statement appeared on the Hearthstone forums, although he did not specify an actual date. Disappointingly, the original plan to release pricing information on 1 July has been delayed for an unspecified time. Although Blizzard has already confirmed that the expansion areas and cards can be unlocked with both real world money and in-game gold.
Curse of Naxxramas is set to introduce an Adventure Mode to the popular online card game. It also brings also 30 new cards to be collected, and Blizzard has already spoiled most of the set on their Facebook page. These new cards are also said to be appearing in packs in the Arena after they are unlocked by the player.
Class specific challenges are also being introduced to allow players to earn new class specific cards. How this will work with the structure of Naxxramas is still unknown; or whether there will be more than one challenge per area in Naxxramas. The Adventure Mode itself will be divided into several five sections, and each will have to be individually unlocked; although the first area is free for everyone.
[Source: Hearthstone Forum]