Blackrock Mountain is Hearthstone's second adventure. Home to Ragnaros the Firelord and his fire elementals, Nefarian and the black dragonflight, and an army of Dark Iron dwarves, the adventure features 5 wings, with 17 boss encounters in total, and provides 31 new collectible cards for players to add to their collections, as well as a new card backs and a new battlefield. The adventure features a Heroic mode and 9 Class Challenges.