Hearthstone single-player adventure mode Curse of Naxxramas announced

Blizzard has announced the upcoming single-player adventure mode for collectible card game Hearthstone: Heroes of Warcraft.

Curse of Naxxramas is set in the necropolis of Naxxramas, which will be familiar to World of Warcraft players. Here Kel'Thuzad is the ultimate bad guy in a player versus environment adventure through five unique wings of the dungeon.

The expansion adds 30 new cards to the game, which you get for defeating the adventure's bosses, which include Maexxna, Loatheb and Patchwerk. Each boss has unique cards and hero powers. For example, the Plague Quarter boss, Heigan the Unclean, has an Eruption spell, which does two points of damage to your left most minion, and Mindpocalypse, which causes both players to draw two cards and gain a mana crystal. The completion of each wing rewards you with a guaranteed new Legendary class card.

Meanwhile, Curse of Naxxramas has its own unique game board, and there are nine unique class challenges, which, according to Blizzard, put a "difficult twist" on existing encounters within the adventure. Best these challenges and you get new class-specific cards.

Blizzard will make Curse of Naxxramas available over a five week period, opening its doors wing by wing. The first wing, The Arachnid Quarter, is free for all players. The other wings must be bought with in-game gold or real money. As each wing is released, the cards available from each show up in your Arena picks, even if you haven't earned them for your personal collection, Blizzard said.

Curse of Naxxramas doesn't have a release date yet, but it will be launched simultaneously for PC, Mac and iPad.