From the very beginning, Blizzard's "Warcraft"-set digital trading card game "Hearthstone" set out to be different. Being in digital format means that they get to do things physical card games like "Magic: the Gathering," "Pokemon," or "Legend of the Five Rings" will never be able to do, and that's mostly through the use of the random number generator, or RNG.
Players have long been divided on "Hearthstone"'s liberal use of the RNG in its mechanics and cards. Countless games of "Hearthstone" around the world have been determined by sheer luck with the game's randomness where most players would prefer to win or lose thanks to skill. It certainly sets the game apart from others of its kind, and while many players would prefer the game to not rely on RNG, Blizzard is completely fine with leaving it in the game, especially during in the middle of releasing its latest solo adventure, "One Night In Karazhan."
In an interview with Polygon, "Hearthstone" associate designer Dean Ayala believes that the cards in the game that rely heavily on randomness aren't the cards that make huge impacts on both the game and the metagame. He claims that they never design "RNG cards" as gamebreakers depending on what the randomness creates (although Yogg-Saron, Hope's End from "Whispers of the Old Gods" can definitely kill you if it casts a damage-dealing spell at you at random).
Ayala, however, still acknowledges the main criticism of the reliance on RNG. They try to approach each card design through the point of view of all levels of "Hearthstone" players, and decide on a final product the best way they can. On this regard, they still try to make sure a player's individual skill is still the biggest factor in how a game goes.
