Hearthstone: Whispers of the Old Gods is an Expansion Pack for Hearthstone and brings an improved gameplay, superb mechanics, and enhanced graphics developed by Blizzard Entertainment, Inc. It offers free-to-play gameplay and features tons of cards each with unique character and spell. In the beginning of the game, the player needs to create his powerful deck by selecting the cards and participate in battles against evils to rescue the world. It mixes the Strategy, Collectible Cards and Turn-based elements and revolves around the battle between two factions, fighting against each another using a deck of thirty cards along their selected heroes with powers. Each player has a limited Mana Crystal, which can be used to cast spells to attack the opponent. The ultimate task of the player is to effort to reduce the health of the opponent to zero and win the level. The game rewards the player with gold for completed each level. Forbidden Cards, Terrorize the Opponent, Upgrades, Magic Spells, multiple Characters, etc. are key features of the game.