Available on Android (reviewed), iPad, PC and Mac
It's fair to say that Hearthstone: Heroes of Warcraft has been a success for creator Blizzard. A side-project to the company's main focus - epic RPGs like World of Warcraft and Diablo - it's a free-to-play card battling title with a degree of depth that perhaps isn't immediately obvious when you look at the often cartoon-like artwork and hear the intentionally amusing voice samples that accompany each contest. However, boasting a strong preference for social play and an almost limitless helping of tactical and strategic depth thanks to the deck editing feature, Hearthstone has become one of the most played titles in the world.
As with all games which achieve this dizzying degree of fame, keeping things fresh is of paramount importance - and Blizzard knows it. The Curse of Naxxramas was the first stab at introducing a fresh challenge, bringing with it a new adventure mode which pitted you against cunning AI-powered opponents, but it didn't bring enough of what really makes Hearthstone tick: new cards. Blizzard hasn't made the same mistake with Goblins vs. Gnomes - the second expansion to the core game - brings with it a whopping 143 new cards to use (compared to Naxxramas' 30), 123 of which are collectible within the game and can be added to your deck once obtained.
To seasoned players, this new alone will get hearts racing. Unsurprisingly for a card battling game, the actual cards themselves are the most important element of any new expansion. With Goblins vs. Gnomes, there are over a 140 new ways of radically changing and altering the complexion of your deck, a deck which will presumably have been refined to perfection since the launch of Hearthstone in 2013.
Figuring out how these new cards fit into your existing battleplan is a challenge which will take many weeks of constant trial and error, and that's half of the fun in a game of this type. While Hearthstone's online play means that matches always have a habit of being unpredictable, with the new cards everything is effectively reset as veterans find new strategies and newcomers benefit from a few weeks of flux in the natural order of things.
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The theme of the new cards is one of invention; both the Goblins and Gnomes are feverish in their desire to create wacky new contraptions, so you'll find plenty of Mech-class minions being played onto the board. Mechs benefit from being played at the same time as other minions of that class, which will surely see some interesting strategies appear over the coming months.
Another new feature is "RNG" or "Randomness", an element which is promoted heavily by these new cards. All card games are based on the concept of luck - you draw cards from your deck entirely at random, after all - but this new aspect could be off-putting for players who don't like the idea of their fate being out of their hands too much.
Some cards can trigger wildly random events that usually end up causing mirth rather than frustration, but there will be times when such an occurrence effectively ends your game. It's possibly too early to tell just what impact RNG will have on Hearthstone as a whole, but for the time being it seems to have injected a much-need feeling of unpredictability to proceedings. And besides, Blizzard can always revise and tinker with cards based on player feedback, so any really irksome quirks can be ironed out over the coming months.
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That's not to say that Goblins vs. Gnomes shakes up Hearthstone entirely; there are some modifications to existing cards - such as cost values changing - but aside from an excellent and much-requested Spectator Mode, things are very much as they were before.
There are no fresh single-player challengers to embark on - as was the case with The Curse of Naxxramas - which means that those who like taking on strong AI-driven rivals before stepping into the online arena may be slightly disappointed. However, that's a complaint that misses the core of what makes Hearthstone so compelling; learning about new cards and finding out which ones are worth factoring into your legendary deck before taking that deck online and testing it against other fans.
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It's also worth noting that with this new expansion comes support for Android tablets and large-screen phones. Previously it had only been iPad owners who were able to take the game on the road, but we tested Hearthstone on the Android-based Nvidia Shield Tablet and found that it performs like a dream. Nvidia is clearly pretty pleased about the new release and has even commissioned some limited-edition Hearthstone: Goblins vs. Gnomes stick-on skins. Compared to the iPad version, it plays wonderfully and by bringing the game to Android Blizzard has opened up the arena to even more players - which should mean that finding a suitable opponent online will be easier than ever.
With over 140 new cards on offer, this is one of the biggest shake-ups in the history of Hearthstone and it has already revitalised the game. New cards mean new strategies and tactics, and if you're anything like us you'll be dutifully honing your deck for the remainder of 2015