Blizzard has announced the next expansion for card strategy game Hearthstone.
Knights of the Frozen Throne, out in August, adds 135 cards to the game and lets you transform heroes into Death Knights.
Nine of those cards are new legendary Hero Cards that, when played, transform heroes into Death Knights. This gives them frost-rimed armor and modified hero powers. There's a new mechanic, too, called Lifesteal. This heals players for damage dealt.
Story wise, you storm Icecrown Citadel and take on the Lich King's frozen fortress. There are a series of free missions that Knights of the Frozen Throne offers to all players. There's the prologue mission as well as Icecrown Citadel's two wings. You fight bosses such as Professor Putricide and Sindragosa. The showdown is with, as you'd expect, The Lich King himself. After completing the prologue mission, you get a random legendary Death Knight Hero Card.
Of note: Knights of the Frozen Throne card packs will be winnable in Hearthstone's Arena mode and purchasable with in-game gold or real money at the same prices as Hearthstone's other card packs.