'Eye of Azshara' trademark by Blizzard signals possible expansion for Hearthstone

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World of Warcraft, World of WarCraft: Cataclysm, World of Warcraft: Mists of Pandaria, World of Warcraft: the Burning Crusade, World of Warcraft: Warlords of Draenor , World of WarCraft: Wrath of the Lich King, HearthStone: Heroes of Warcraft
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PCGamesN