Hearthstone

Set within the Warcraft universe, Hearthstone is a digital-only, turn-based collectible card game which pits two opponents against each other. Players select a hero from one of eleven classes. All classes have unique cards and abilities, known as hero powers, which help define class archetypes. Each player uses a deck of cards from their collection with the end goal being to reduce the opponent's health to zero.

There are five different types of cards: minions, spells, weapons, hero cards and locations. These cards are ordered by rarity, with Legendary cards being the rarest, followed by Epic, Rare, Common, and Free. Blizzard releases expansions of additional cards every four months, as well as smaller mini-sets between expansions, to increase the variety in the metagame. The game uses a freemium model of revenue, meaning players can play for free or pay to acquire additional card packs or content.

Hearthstone was developed by Blizzard Team 5 and published by Blizzard Entertainment. The development of the game was inspired by two directions, according to developer Eric Dodds: a desire for Blizzard to develop something more experimental with a smaller team in contrast to their larger projects, and the shared love of collectible card games throughout the company.

Blizzard executives, around 2008, had considered that their revenue was primarily sustained on three well-established properties (the Warcraft, StarCraft, and Diablo series), but saw the rise of small independent developers with highly successful projects, representing a shift in the traditional video game model. To explore this new direction, Blizzard brought a number of people into "Team 5", named after being the fifth development team formed at Blizzard. Initially, the team had between 12 and 15 members, in contrast to other Blizzard games with teams in excess of 60 members. By November 2015, the team had 47 members.

Hearthstone received "universal acclaim" on iOS and "generally favorable" reviews for PC, according to review aggregator Metacritic. The game was praised for its simplicity, gameplay pace, and attention to detail along with being free-to-play, while the lack of actual card trading between players and any form of tournament mode was pointed out as the major shortcomings.

Eurogamer gave the game the perfect score of 10 and remarked that the game is "overflowing with character and imagination, feeds off and fuels a vibrant community of players and performers, and it only stands to improve as Blizzard introduces new features, an iPad version and expansions."