Everything about developer/publisher Blizzard Entertainment, the studio behind World of Warcraft, Starcraft and the Diablo series, is enormous. Its Californian HQ is guarded by a huge iron orc, the employees have giant personalities (often matched by beards), and even the cafeteria's portions seem otherworldly. It's a studio that operates on a scale beyond almost any other. Which is why it seemed a little surprising that, earlier this year, Blizzard announced its next title would be a card game: Hearthstone: Heroes of Warcraft.

The name drives home a point. The old idea of a hearth as a place of friendship and warmth, a promise of an intimate world rather than a moonshot at the universe. "First off it wasn't just you," says Jason Chayes, the production director of Hearthstone. "We've had a lot of feedback about that. Hearthstone began like all our other games which is to say we start with the games we are excited about here, what are the games we're playing in our lunchbreaks or with our buddies at the weekend, and for a very long time now Blizzard has been a place where there are a lot of collectible card game players."

Hearthstone: Heroes of Warcraft: 'We wanted you to almost feel those cards'

"So there was always that thought of doing our own on the back burner," says Chayes. "A few years ago there was an idea to set up a new development team we're calling Team 5. There was an awareness that we have all these large teams working on huge projects, and we don't really have the capacity to jump on cool new opportunities as they come up. So once we committed the resources to that and began kind of spinning up development it became what they call a 'no-brainer' – it coupled our passion for card games with this smaller more scrappy team size. So that's where Hearthstone came from."

CCGs head online

Collectible card games (CCGs) are those in which a basic set of cards is supplemented over time with expansions containing new cards and strategies – both an exciting prospect for long-term players, and a killer business model. CCGs are a $2bn market worldwide and, though at the moment the money is still mainly in the physical realm (think Magic: The Gathering), the digital slice is ever-growing. Indeed, online is an area where the traditional big hitters have left the field open to a host of newcomers such as Cygames' Rage of the Bahamut.

Blizzard is a new calibre of entrant. "With Hearthstone we knew from the start this would be a game to be played online," says lead designer Eric Dodds. "We realised over the course of development that a lot of the old physical conventions of card games just don't work so well online – so one example is turn flow, where you have actions that respond to actions which are then responded to and so on. That works pretty well when you're sitting at the same table as someone, but online that adds a lot of complexity and a lot of staggering – starting and stopping constantly, which doesn't feel good. So there are things common to all CCGs, but overall Hearthstone is its own thing."

Eric Dodds: 'We knew from the start this would be a game to be played online'

The most striking aspect of Hearthstone, initially at least, is the feel of the thing. Blizzard are masters of making a player's inputs feel crunchy and connected to the in-game action. Hearthstone starts with your opening a tactile box, and during matches the cards waver and move in your "hand", before slamming down on the board with great thumps. Even if Hearthstone wasn't a good game – and it's a very good game – the simple act of toying with it feels fantastic.

"I guess one of the things we talked about a lot while designing this game is making sure that it felt physical," says Dodds, "because when you're talking about card games that are in the real world we talk about opening the packs and shuffling and the new card smell and all these very visceral responses. So when we started working on the online game we wanted to keep the soul of that which is why we made the box, and the cards in the way they sway as you're moving them through the environment, and the buttons that feel and respond like physical buttons. We wanted you to almost feel those cards and that box in your hands even though it's a digital construct."

Business model

Hearthstone is currently in beta, an increasingly common way for online multiplayer experiences to be stress-tested before hitting the wider audience, but already feels like a finished product – Chayes says players can expect "one more level of polish" before release. At that point Blizzard will give away the game for free, and hope to make money from selling additional card packs and expansions.

"In terms of business model we normally start with the game concept first," says Chayes. "So Hearthstone began as making the best card game we could make. And when you have something you're happy with you start looking at your options in terms of business model, and in Hearthstone's case one of the aims was to keep it accessible – so with free-to-play people can try it for nothing and more importantly have the option to continue playing it for free. We don't have any paygates, there are no portions of the game impossible to access without real money. What spending money really gives you is the opportunity for quicker progress, so we have the Arena where you can either pay to enter or you can earn the currency in-game."

The Arena is the only slight downside I found to Hearthstone's business model, and rather counter-intuitively this is because it's the best mode in the game. Upon entering the Arena you construct a new deck from pre-selected cards (different every time) then use this deck to battle other Arena opponents – each win makes your eventual prize better, while three losses means you're out. This costs either £1.49 or 150 gold to enter, the latter being an in-game currency gradually accumulated through completing challenges and winning games.

Hearthstone: Heroes of Warcraft: will players be happy to pay to enter the Arena?

The problem being that the drip of gold from playing is too slight to fund regular Arena entries – so you end up paying. This is always a delicate balance in free to play. Speaking as a consumer I'm happy to put money into Hearthstone for card packs at intervals, but not so happy to have to pay every time I want to play my favourite mode. In Blizzard's defence your Arena prize always includes at least one pack anyway, but such an argument pre-supposes you'd only play Arena for the prizes. Still, worth remembering this is not yet the final product.

Chayes's point about keeping Hearthstone accessible is broader than the business model anyway: "This is a genre that hasn't really had the chance to break out to a mainstream audience. And that's a big focus for us internally, we believe there's such a fun core compulsion there in CCGs and maybe that fun's been buried a little deep. So with Hearthstone we want to peel some of that back a little, keep the depth of the game, and expose it to a much broader audience. We really think anyone can play this."

Hearthstone is certainly a game that explains itself well, and the visual language is exceptionally clear, but the facts suggest Blizzard will have a tough time broadening this particular market. In the US, at least, just under 90% of digital CCG players are male and the average age is 21 to 22. One could call this an extremely traditional market for digital products.

'Perfect fit' with Warcraft

I wonder whether, if accessibility is a core goal of Hearthstone, a fantasy world like Warcraft is necessarily the best choice of "wrapping". "Warcraft is a world that an awful lot of people know about," says Chayes. "So many people have become so immersed in the Warcraft world, and there's hundreds and hundreds of characters and places to draw upon. That's very important when you're making a CCG because not only do you want lots of different characters and locations players are familiar with, but you want them to have a connection too – and we've been seeing that as people have been playing Hearthstone, many are having this wonderful sense of nostalgia and getting super-excited about characters they remember from back in the day. It's a very rich and broad world to draw on that has tonnes of people already excited about it. So it seemed the perfect fit."

The emphasis on character also feeds into one of Hearthstone's key design decisions – making your avatar a part of the action through "hero powers". In games such as Magic you basically play as a disembodied health bar summoning monsters, but in Hearthstone your chosen character can intervene in the game directly, by for example taking out an enemy minion with a fireball or sacrificing some health to draw an extra card.

Jason Chayes: World of Warcraft is 'a very rich and broad world to draw on'

"When we were working on the game initially we wanted to make sure that the heroes felt like they were concretely connected to their Warcraft counterpart," says Dodds. "So [the powers] make you feel that the priest is a healer for example, or the rogue stabs people, or the warlock is draining his own life for power. And while you have this stack of cards, that power really defines and helps that hero work – and from a design point of view are important, because when a player is choosing what action to take they look at their cards and the cost of their cards, then they look at their hero power and its cost."

Hearthstone is not the first CCG to embody the player character in this way, but it remains a risk for the game's balancing – as you play more, there are cases where hero powers swing the balance in a manner that can feel frustrating. "The powers are all built at cost two because that means you can often combine them with cards," says Dodds. "So the combinatorics and complexity of the game become much more interesting with that hero power, because it's no longer 'Oh I have five mana so I'll play this five mana card.' Now you might play a card with cost three and use your power, and that might make for a better tactic. So it makes for a deeper game. And while our goal is to make a game that everyone plays, it's also very important that it retains depth because this is something we intend to support and want to see played for years to come."

Typical Blizzard – this is a company known for not only the outstanding quality of its games, but its ongoing commitment to their communities and content. Hearthstone will be no exception and, despite the intimate name, already feels like a top-in-class CCG. A brutish comparison this may be, but none of the competition is even in the same league in terms of look and polish – a metric that carries more weight with players than any designer likes to think about. Add in the fact it's free and anyone who thought of this as a small project for Blizzard may well be eating its words ... soon? "You can expect one more meaningful patch [for the beta] with some cool features," says Chayes. "But we're getting pretty close now – we've said in the past it's our goal to get the game out this year, and we're feeling good about hitting that."