Good news for any fellow Hearthstone fans on here, more details about the game's upcoming first expansion have been released, including pricing.
The Naxxramas PVE "Adventure Mode" will be split into five "wings," each of which will feature multiple bosses which World of Warcraft players will likely recognize from that game's corresponding raid, Naxxramas. The Arachnid Quarter, for example, will feature the bosses Anub'Rekhan, Grand Widow Faerlina, and Maexxna. These bosses will feature unique abilities and cards which have not yet been added to the game, some of which will be unlocked by defeating them.
The five wings will be unlocked weekly. Anyone who logs into the game during the launch event will receive the Arachnid Quarter for free. The following four wings will be gated, unlocked each week following release, and will be purchasable for either $6.99, or 700 gold (earned by playing the game). Lower pricing is available for buying all wings together in a "season pass" fashion.
For those looking for a greater challenge, once the normal version of each wing has been completed, the "Heroic Mode" of that wing will be unlocked. Those who are skilled enough to defeat all five heroic wings will unlock a unique card back.
If you're looking for the shiny gold versions of the new cards though, it sounds like there's some bad news coming. The cards exclusive to the Naxxramas set will only be available in gold via crafting, according to a Blizzard response over on Reddit. It's still subject to change, but for those who've tried earning the 3200 gold required for a golden legendary, it's a pretty discouraging response (especially since it's supposedly being done in the name of keeping the gold cards "accessible"). Hopefully they'll change it to being unlocked by defeating Heroic Mode wings, or as a chance-based drop, in addition to crafting.